I am using 1366x768, which was set through the widescreen mod during install. I left the BGConfig resolution at 800x600.
Other miscellaneous info, I am running a 64-bit version of Windows 7. Also, I installed the game to the Program Files folder on accident, and then read something that said I could just copy it to another folder, which I did. Would that affect it at all? I did change the location references in the baldur.ini files.