Use Win 7's "System Restore" to restore the system to the state it was in before you first installed the game, then try again.
You don't mention any error messages or error codes so I can't comment on what the problem was, or what Daemon Tools wanted you to change in the registry.
i brought a game a couple of days ago (final fantasy viii) i installed the game and all, and had a problem with the cds instalation because my laptop cd-rom is not working so i was using daemon tools and this required me to edit something from the regedit, in which i did, but there was a problem with it so i tried to uninstall the game a couple of time but still no use and while i was doing so i noticed that the game file on the regedit didnt change in anyway so i thought that it was the problem, so being smart as i am i decided to delete the game information from the regedit, and re-installed the game, but the problem was the game is not on regedit anymore and i tried to re-install it a couple of times but there is no use, i even tried to restore my pc but still no use... please help me out with that i waited for to long to play this game again.
what i want now is getting the game back in regedit!
thank you in advance