Don't worry, even if you can find the BIOS on your Dell, you won't be able to hurt your computer.
They give you so few options in the BIOS that I would be suprised if C&Q was one. I disabled the C&Q for my OC'ed FX-60, but it probably wouldn't hurt if your CPU isn't OC'ed to leave C&Q on. The CPU speed should go up to full speed when an application or game is running. If you want to check, run a processor intensive app like a virus scan then recheck processor speed.