I got my first computer in 1985, a Commodore 128. Then a Toshiba T1850 in 1993 and a beige box desktop PC in 1998. I bought several more PCs since then, and tried my first Mac in 2002. Now I have a PowerMac G5 (2005).
The C128 was wasted, a C64 would have done it equally. The Laptop was overpriced, and the only reason I bought it, was so I could put from my desk into the drawer. Man, a 386SX in 1993, when the Pentium came out. Also, all the fiddling with the PCs, different iBook, PowerBooks, and the mini...
With the benefit of hindsight I would change it: I would buy an Apple IIc first. It had lots of software then and was a lot cheaper than an IBM PC. Or would have been an Amiga 1000 the better choice? A NeXTstation would have lasted the whole decade of the 90s without feeling out-dated (ok, it would have cost 3x as much as my Toshiba). After that an Apple Cube to wait for the transition to Intel in style...
What would you change about your computer acquisitions?