Once you see the “Bethesda Softworks” logo video, the game is already loaded, and the cache should have been cleared.
Note, this does not effect your game in any way other than loading. You will not lose any saved data.
Also check to make sure the disc surface is free of dust and smudges, even a light smudge can cause the game to load slowly or lock up completely.
If the above doesn't work try removing your hard drive completely.
If that doesn't work, or you don't have a hard drive, you're experiencing a completely different problem and should probably contact MS.
Edited by twistedsymphony, 13 May 2006 - 07:35 PM.