What exactly do you want this DI box for? Your electric guitar?

I have taken direct injection of my guitar without one and I can get it to sound good, but it takes a lot of Plugs and EQ's; you know, bass filters exciters and the like.

I think you've mentioned having an amp and microphones before? If you were playing an acoustic electric guitar live then I'd say get a direct box. Otherwise, a quality preamp is a better investment if you ask me. And then there's recording bass guitar direct (I'm guilty of being a cheapskate when it comes to bass gear)... A direct box could work, but still, a good solid state preamp is a better idea if you ask me.

There are a number of reasons to use a DI. When running long cords on large stages changing an unbalanced to balanced signal or any other time we need that type of change. When the next stage of amplification requires a different signal strength, ground loop interuption and a number of other reasons.
There are different types of DI boxes, passive and active for example. Basically a passive ones uses two isolating transformers unpowered to change unbalanced to balanced or vice versa (they can be used in either direction.) http://www.sweetwater.com/store/detail/ProDI/

Then there are active DI's that offer a slight boost, work on phantom or other power sources, have much better transformers (generally) and more features like an industry standard such as
http://www.sweetwater.com/store/detail/DT85/

There are many variations but Remy swears by units with Jensen Front end transformers (FET) like
http://www.sweetwater.com/store/detail/JDI

Its sorta like asking why are there so many mics?
Each has its devotees, uses, and level of quality.

Just so you know your Presonus has an instrument ready channel or channels and does not require a DI box because it has sufficient gain stages in the preamp, this is not true of all preamps, mixers, line amps etc.

Yes I am planning on using my electric guitar with the box. I am planning on taking a line in as well as miking my amp at the same time. I've done it before using this... link removed not for the distortion just because it has the amp out and DI out. But the DI sounded truly butt, like I said before it took a lot to make it sound good, but when I was done the tone was there. It was like the two tones were compliments of eachother and came together nicely. Just thought maybe a DI box would take this to the next level.

I want to experiment with getting huge guitar tone. Maybe using two mics and a DI at the same time just get huge wide open tone. I started another thread earlier about preamps and pretty much got shot down by people saying a preamp won't do anything good for me at this point. (sad face) to be honest I still want one though lol. IDK, maybe we can open this discussion up to preamps as well. Well I've made my goals clear, you guys would know better than I what it takes. What say you?

There is another reason to use one splitting a signal, though in a home studio you could also use an A/B/Y box.

Sometimes using a DI in conjunction w/ a mic'ed amp provides a nice guitar tone. You'll find the DI sound to be cleaner (soulless, imo), and having more auxiliary sounds like finger/string/pick noise, etc.

For those reasons, I've gone away from using the DI tone directly. I still do take a compressed DI track and slide it in under the mics for "reinforcement" sometimes.

Here's where you really need to pay attention: There's an even better use for a DI in your case.

Take that DI track, and reamp it. Different amp if you have one, different mics/placements for sure.
That will also help give you more guitar sound. Or bail you out if an amp craps out or just plain sounds bad. Or if you're doing a full band and don't have enough channels to mic all the amps the way you want to. Since I've only been doing this a couple of years, I like to cover my butt. DIs help me do that.
Note: This would require a passive DI (to run it in reverse), or a reamping box. Which is kind of overpriced if you already have a decent passive DI.

Is a passive DI box similar to passive monitors in the sense that there is other things needed to power/control it?

The opposite.

Re-read jg49's first post in this thread.
He does a nice job of explaining passive/active.

I also 2nd the JDIs w/ the Jensen xformers, a la Remy.
I've got a couple of B*r active DI boxes that I never use unless I have to.

I like the first link that jg posted, at least my wallet agrees with me. How will something like that compare to Remy's preferred model for almost $100 more?

JG49.....FET= field effect transistor....not front end transformer.

All your other info is dead on.

Radial makes great gear. The difference in price reflects the difference in options.

My 2 cents:
As far as the extra $ for the fancier DI, I don't think you'll hear a difference. As long as you avoid cheap-o brands you'll be fine. Radial & Whirlwind make several great boxes for under $100. I'm a live-sound engineer by day, and I love the Whirlwind IMP (~$50) because they are very small, include a ground lift switch and parallel 1/4" out, & DON'T require phantom power.
To clarify the active/passive point: an active DI requires external power, either AC, battery or phantom 48v. By being powered, the box can convert the signal with less distortion, so the audio coming out is as hi-fi as possible. A passive DI, therefore, doesn't need power but also doesn't have the best sound quality.
I tend to go with passive DIs because I don't hear the difference, and in live sound situations, I don't like using any more phantom power than I absolutely have to. (It's one more thing to go wrong, and if a phantom-powered cable gets wiggled or has a short, it can cause speaker-blowing pops.)
Now, if I was recording Clapton on a Martin in a pro studio, I'd want the i fanciest DI I could find. BUT I'd mainly be using it to SAY that I used it. I have A/B'd the IMP vs expensive, Jensen-based DIs, and I felt that the signal quality was very very close.
If I were you I'd drop $50 on the IMP, or maybe $100 on the passive Radial. If your wallet can stand it, grab the $100 Radial RMP re-amping box. As mentioned by soapfloats, if you record straight into the session (either direct to the board or through a DI,) you can send that recording through a re-amp box, back out to your amps or pedals. This brings the line-level signal from the Presonus back down to guitar level, essentially a DI box in reverse. (as soapfloats says you can pull this off by going backwards through most DI boxes, but a "real" re-amp box will do a better job of impedance-matching without messing with your tone.) Once its back down to guitar-level, you can feed it into your amps & effects, without having to turn their gains & volumes way down. This lets you record the performance once, but still have endless options for trying different amps & FX. You can take the same performance & create overdubs using completely different tones, which usually works well for creating huge walls of guitars. Very useful for a guitarist who is recording himself, or if you just like having options.
To make a long story short, I recommend getting a good passive DI for $100. If you can afford it, get a $100 re-amp box as well, I think it will give you much more satisfaction than putting the extra $100 towards an active DI, which probably won't sound $100 better than the passive.

Ok Dave, sorry I hate technical gaffes, I try really hard not to dispense incorrect info.

This is a quote from Remy
"Guitars with passive pickups need to see the high impedance load that tubes provide. A DI transformer will generally not be higher than 50 K ohms. It will affect the tonality. But an active pickup with a JFET input will present the pickups with the proper load, high. And you'll probably need to power that active DI with an internal battery, since you will not be providing phantom the box. "

In that instance the JFET is a solid state device driving the front end of the DI. It is used in conjunction with the transformer output. Like she said and this is the gist of her post, the guitar pickups will want to 'see' a million ohms if posible so theres no 'loading'. The transformer in this case provides some tonality to the output as well as the impedance and voltage characteristics needed to match the input of a console or other recording input. This would be an 'active' DI, and would require power of some sort.