Ixamyakxim: While I've junked a lot of my old computers, I do keep around a decent Win XP box just for cases where I have a hankering to pull an old set of discs or CDs out and give them a try. Between DosBOX and native XP, hasn't given me any issues yet!
JinseiNGC224: If I wanted to own a computer (or multiple machines) that could run any game from the late 80's to the early 2000's, what operating systems should I aim for?
I'm no expert in this area... but the machine I have for old stuff is a Win XP Celeron or P2 (clocked at about a gig or so?), running either onboard graphics card or maybe something in the TNT 2 arena? Circa '98 - '00. Ram... I have no clue, though I could check if you were interested. I don't know about Amiga emulation, but this thing has had no problem running anything in DOSbox or from early Windows. I've tossed X-COM 3.5 discs at it, X Wing Alliance, Privateer, the classic iso-CRPGS (Baldur's Gate, Torment) and I really haven't had to do anything to get things running. The most difficult thing I've had to do is mount the drive in DOSbox. No messing with CPU cycles because the game ran at 1,000 MPH, no registry hacks, nothing. Obviously your mileage may vary but mine has done well as a "legacy" computer. 'Course, now that I'm on GoG it's been a bit easier to use my "real" PC, but this old dog has done me well for all the old discs I've pulled out of my basement.
The one exception... Vampire: TMR. After a patch or two I got it running but there's an early "level" that takes place in dark caves... for the life of me I couldn't get the game to adjust brightness in a way that made the game fun to play. Way too dark no matter what I did.
*and EDIT to add... Ah yes between my friends from long ago and I the Compaq Presario has many, many fond memories. I know it's probably committing some sin but this computer should rank up there with the 2e and a few others for "machines that should hold a special place in all gamers / computer nerds hearts" ;)