It's a real shame that a lot of older games are no longer playable on modern machines, as some real classics are in danger of being lost, unlike any other media I can think of (books, music), where it is relatively straightforward to move the content from one format to another. I can only speak from a Mac perspective, but I've got three classic Blizzard games (Starcraft, Diablo II, and Warcraft III) on my ageing MacBook, and while I'm stretching its lifespan as long as I can (mainly for financial reasons!), when I inevitably upgrade I know that those games won't work on newer versions of the Mac OS. Given that's three-quarters of my games library (the other quarter being Civ III!), it'll suck!
Sad to hear about C&C95, too - I got my old copy to run on my mum's Windows XP, but sounds like even that will be a thing of the past before too long.