Gary, an IMAC over a PC because it's a good deal more bulletproof.
Less than a year ago, Julie bought a new Dell laptop PC for her work (she works from home now), which runs Windows XP Professional. She's had nothing but trouble with the software, constantly getting the "blue screen of death" and such. She's also had hardware problems, needing to have the hard drive replaced immediately. Her son has built his own PCs for years, constantly having trouble with them, but got disgusted and finally bought an IMAC half a year ago. Not a single glitch. So Julie bought one a month ago and hasn't had a single problem. Yet the stupid Dell PC, even though she uses it only a couple of times a day, for certain things that the IMAC has no software for, still crashes with the blue screen. Pretty much everyone who buys an IMAC loves it. It will even run most Windows programs. On the flip side, I've never had a MAC but have always built my own PC from components -- the most reliable components I can find. I never have hardware trouble, but constantly have something stupid happen with the Windows software. But I don't do nearly as much diverse stuff as Julie does -- just run Internet browsers, Word, text editors and so forth. If it weren't for the fact that I like to tinker with the hardware, I'd have gotten a MAC a long time ago.
AlanF