I'm not too conversant with the current generations of Mac's but your processor/ram is sufficient. The majority of issues with Mac's have to do with whether you have a firewire port or not and/or an express card expansion slot.

What exactly is an an express card expansion slot?
My computer does have a firewire port but i went to Sam Ash and asked the manager of the Pro Audio department about interfaces and he told me that USB 2.0 is actually faster than Firewire and told me to go with the M-Audio Ultra. I tried asking about things in a slightly more advanced price range but he insisted on the M-Audio USB Interfaces.
Will that be good enough?

USB 2.0 is not anywhere near faster than Firewire except in a theoretical fashion. The guy at Sam Ash doesn't actually know anything. If he did he wouldn't have given you an outright falsehood. USB is also a "dumb" interface while firewire is more of a managed interface to put it in simpler terms.

Most things in the budget 2 channel range will sound roughly the same but I really dislike the budget M-Audio stuff. Almost as much as I dislike all the Alesis "interfaces." Someone that is pushing one particular unit usually has an agenda or that is the only thing he has used (so it must be the greatest right?).

Now, having spewed on that, for two channels or one channel the USB devices will work as long as you have a USB 2.0 port on your computer.

OK, lets say for instance that the guy was correct in that USB 2.0 is faster. But it's a one way street, the other lane is clogged to its limit. USB does one way very well, and the opposite way is molasses. FireWire is balanced in both directions, allowing the two devices to speak and interact with eachother more efficiently as god intended.

I guess I'll see how it goes! I'll probably upgrade it later.. Right now I'm just concerned about my computer..
So my Macbook will work fine?

It should be fine, as in not the weakest link at this point.

Alright.. thanks!

form what i have just read, the macbook pro has the texas instruments firewire chipset. I dont know if i read this wrong but it said 5400rpm on the hard drive,... isnt 7200rpm ideal?

Well in an ideal set up you are working with two hard drives one for the OS and DAW software and a seperate one for recording, and yes ideally that one should be 7200 rpm.

just picked up a macbook pro 2.26 the other day! Quite excited to start using firewire. not just have to get the duet and ill be on my way!