Until recently I've never had any problems playing older Windows games on my laptop. Most would work fine by default, some I had to run in compatibility modes, but they all worked.
Then, few weeks ago I tried installing Battlecruiser 3000AD, and it screwed something up. Newer games, like Spore and Witcher, they work fine, but none of the old Windows games will work any longer. Whenever I try to run them, my cursor turns to an hourglass, showing that something's loading, and then it just sits there. Nothing freezes, it just won't run those games.
Any idea what could be wrong, or how do I fix it? As I said, these games used to run fine, and nothing has changed on my system - no new hardware, no configuration changes. I''m running Windows 7 Ultimate x64 on my laptop, with Intel i5 2.27GHz and 4GB of memory.