For casual internet, e-mail, and MS Office Word & PowerPoint, is there much of a difference between a "first-gen" 20" Intel iMac and a current low-end iMac? I'm not sure if there is much of a functional difference between the two, seeing as they both have Front Row, webcam, and dual layer SuperDrive... except for the difference of matte (preferred) vs glossy screens. 
I'm guessing that speed benchmark differences don't come into play for such casual use (i.e., both computers would be running near-idle most of the time).
I'm guessing that speed benchmark differences don't come into play for such casual use (i.e., both computers would be running near-idle most of the time).