Games refusing to run.

I've tried many a things to fix this problem, contacted the game's tech support, scanned the internet, and I've still yet to find a solution. Any assistance at all would be greatly appreciated. Apologies if this is the wrong category.

Games that refuse to run:
-Company of Heroes + First expansion
-Neverwinter Nights II
-Fallout III

Games that run:
-Assassin's Creed
-Left 4 Dead
-Team Fortress II
-Farcry II
-Unreal Tournament III
-Spore

Specs:
-Intel Core 2 Quad @ 2.4GHz
-Asus Striker Extreme Motherboard
-4gb RAM
-MSI 9800 GT

Issue:
All these games are legit. I say this because I've been told that Securom might be the problem. I purchased Fallout III the day it came out, played through it and beat it. Recently I went back to play it and it refused to run. It was never uninstalled. Company of Heroes I was actively playing online with friends when one day the game simply would not run. Neverwinter Nights II I uninstalled and recently reinstalled. It too refused to run.

When it refuses to run:
I can explore the CD, I can run setup from the CD and install the games. I can uninstall them. I click on the short-cut to play, mouse goes hour-glass then simply stops. It is not running in the background, and I've watched the processes appear for 1-2 seconds then disappear.