you may have already tried what im about to say but if i was in your shoes i would:
check that all my
drivers are up to date and the latest ones for Windows 7.
patch the game to latest version, i know this doesnt help on the Windows 7 funny colours problem but still, its worth doing.
Close all unneeded applications
run the game
if still black screen post back here so we know
if you do get into the game, you might want to track down the thread about AoE2 colours being weird, thats another problem then, but we know how to solve that one.