With my computer, if I want to run ANY games, not just old ones, I first need to turn off the little program that runs my "extra features" for the infrared keyboard/mousse I use.
Maybe you've got something similar you can turn off before trying to run it ?MM7 runs for me just by doing this, but there are some games (Diablo 1 and C&C Red alert 1 for example) that still won't run for me, so I got my friend to create a "dual boot" machine for me.
To be honest I don't know exactly how he did it, but he was only at my house about 2 hours and I didnt spend any money!!!
(Theres loads of info on the internet about how to do it)
The result is that now when I boot my PC, if I do nothing it loads into XP, and if I want to play one of my "problem" games I simply press a key during boot up and it loads win98 for me instead, all but one of my games works fine in win98 "mode"
The only downside of this approach is that it does take up a lot of disk space, having 2 OS's and of course 2 sets of drivers for all hardware (also, win9X drivers may not be available if you have really new hardware...)
A bit extreme perhaps, but it worked for me
