Thank you both for your replies. I've just finally upgraded my PC to Windows 10 (from XP), and it looks like i've got to replace most of my old disc-based games.
There are workarounds for a lot of games; see the specific subforums, search the internet or ask.
But yes, some games will never work. You can either keep your old, if still working, computer for those or install Linux + Wine next to Windows and have a good chance they work in there, not 100% though.