Advice needed.

Well first, do you want something portable or not? There's pros and cons to both, but you need to decide first I think.

 

If you get the Edu discount, then you're probably a student. If this is the case, go for the portability of the MacBook. It will serve you better over your studies.

But then, you also have stated your needs. Do you need the capabilities of a desktop unit, and the extra screen real estate that comes with?

 

As a student a laptop is very very handy. Whether you want to bring it to group project meetings, or just the in the library, it's quite handy to have

 

My MacBook Pro has been an invaluable addition for college (especially since I am a commuter).

 

Macbook vs iMac? I think this decision comes down to two things...

1. Do you need to have you computer somewhere other than your desk?
2. Do you need lots of storage space?

If you won't be traveling with your computer and you do need more storage space, you'll want the iMac. If you need to travel, and storage isn't an issue, roll with the Macbook. If you need travel AND you need storage space, well, I'd go with the Macbook and get a smaller external drive that you can carry with you (and one that's bus-powered so you don't need an external PS for the drive).

Just my $0.02.

 

Basically, what everyone else has said is about right. The computers themselves aren't that far off; you get portability with the MacBook, and a bigger hard drive with the iMac (along with a larger screen).