While you are free to experiment, and I have tried to only include 'safe' working tweaks here, bear in mind that you can get some unusual results and perhaps experience odd problems by making too many changes, so take things slowly and test the effects of the tweaks using a few different saved locations to see if they are working correctly for you - different systems will exhibit differing results. Please pay careful attention to how to implement these tweaks, and read the instructions on what they do closely. ini file adjustments, while the Console Commands section deals separately with using the in-game console. There are two main ways to tweak Oblivion variables - the initialization (.ini) file and the in-game console. Furthermore, there are a range of parameters users can access and alter to change the way the game looks and acts. Fortunately, Oblivion has been designed for user modification (or 'Mods' - see page 4 of the guide), which make complex gameplay or graphics adjustments relatively simple to implement. While Oblivion has many in-game options for adjusting visual quality and performance, that's not where the tweaking stops.

Elder Scrolls IV: Oblivion Tweak Guide Advanced Tweaking