Vista - Bad uninstallation of game, so won't let me install it again

I recently uninstalled a game (using the uninstaller) and as far as l could
tell the uninstallation went well, all of the files were deleted etc.
However, coming to install the game again l've found my PC still thinks that
the game is installed (it still appears under Programs and Features.)
I can't select install on the CD's autorun, l have also tried manually
looking at the CD's files and selecting "setup" but this just runs an
uninstallation program that makes no difference. Selecting to remove the
program from the Programs and Features also makes no difference. I have tried
everything listed on the windows help website and couldn't find something
that worked and the developer has no information on this subject.
Basically is there a way to tell my PC that l have already unistalled the
game? Or anything left that might be telling my PC otherwise?

I'm using Vista Home Premium and the game is Baldur's Gate 2

Cheers!

check where you installed the game to (the directory i.e. C:\games) and delete any trace of the game from there, then delete all your shortcuts from start menu, then open the run command (windows key + r) and type in regedit. (click continue on the UAC prompt) and hit CTRL+F and type in baldurs gate. Delete everything that comes up...

OR, if you dont want to, or that doesnt work... download CCleaner, and install it. theres an add/remove programs list, that lets you remove the programs from the list, will stop annoying you at least.

You may need to open the system registry (Start->Run->type: regedit and press the Enter key.

Now, under File, select Export, give the file a name. After the registry has bene backed up, press the "F3" key. Type Baldur's Gate. Delete all entries you find. Pressing "F3" again will search for the next entry. Once your done, exit the system registry and try to install again.

Yo might also want to defrag your hard drive. I've seen fragmentation cause problems, not neccessairly with vista, however.