Can't start game

[contempted]

I just bought Civ 4 a few weeks ago, it worked fine and then suddenly I couldn't get the game to start most of the time. When I press play game a black screen comes up with the warriors face in a circle about an inch around, and them the monitor says something about "no input" and goes to sleep ,and then I have to restart the computer. Sometimes if I'm luck after 10 tries or so, I can with a mixture of hitting the hibernate button or ctl alt delete, I can get the game to start, or at least not to crash the computer. When I try to install 1.74 patch it won't, and then it I even had to find a free uninstaller to reinstall the game since the computers uninstaller wouldn't take it off. Once I get a game started it runs fine, and I can load saved games subsequently. Any ideas?