We need more information about what games you're trying to play.
If you're trying to play a DOS game, it will have to be played using DOSBox or ScummVM -- unless it's an updated version that has the DOSBox or ScummVM already built into the installer.
If you're talking about Still Life or Post Mortem, they don't work on most Windows 8 computers (which is why GOG and Steam don't support them on Windows 8).
Most games that work on Windows 7 will work, but some of the older ones need compatibility mode, or to be run as administrator, or to be installed some place other than C:\Program Files or C:\Program Files (x86).
If you're talking about a new game, but your computer has a video card that doesn't meet the required spec, the video card will have to be updated. If the video card does meet the requirements, it may need different drivers, possibly newer, possibly older.
If you're talking about an old 1990's Windows game that uses an old version of QuickTime, that's a whole other can of worms. Some of them can work with newer QuickTime, but some can only work inside a virtual machine.