I recently got Oblivion on Steam for my Windows 7. Everything went on as it should until I installed the FCOM mod (and all there is to it), the installation was succesfull as I could still start the game without any problem and play it. But I wasn't satisfied with just FCOM so I downloaded some more mods and installed them using OBMM, but this time the game would crash as soon as I saw the Bethesda logo. This continues to happen even after I've been unistalling and installing over and over again. (4 times this far.) So all I'm asking is: Is there a way to reset all the changes Oblivion does to your computer for a clean install or does anyone have a better idea?

When uninstalling, did you make sure to delete the Oblivion.ini in My Documents>My Games>Oblivion?