Note: I am not sure if this works, but I am posting the information here anyways, in hope that it does. Please let me know if there are any problems, or side effects from this strategy.
If you have been experienceing long load times for The Elder Scrolls: Oblivion, then you might have too much stuff all spread out on your hard drives (called fragmentation). This is supposed to be rare. And so things don’t load into the cache correctly, and sounds and menus can load too slow.
There’s a harmless solution for this: “To solve this problem, reset your Xbox, and hold down the A button as the game is booting up. If any button is held while Oblivion is loading, it will clear its hard drive cache, and create a new one. Once you see the “Bethesda Softworks” logo video, the game is already loaded, and the cache should have been cleared.”
Source: TES Forum