Did you try just leaving it for awhile, to see if the loading process was just longer than normal?
Is your anti-virus program, or something, set to automatically update in the background? That could cause a conflict even if you didn't manually install or change anything.
Are you shutting down all non-essential programs before starting the game?
When you uninstalled the game, did you make sure there was nothing left in the Divine Divinity folder, other than possibly the savegames folder, before rebooting and reinstalling?
Each save is a separate subfolder in the '..\Divine Divinity\savegames' folder.
Under Vista/7, depending on how the user accounts are set up, if you install the game to the default Program Files path, Windows can create separate savegame folders for each user, and then map that folder to the game's savegame folder (so it will just see the saves for the relevant user).
C:\Users\ %account name% \AppData\Local\VirtualStore\Program Files\Divine Divinity\savegames
If you installed to the default Program Files path, you could try re-installing it elsewhere (like in c:\games\ or something).
