No probs. I had a feeling you and 'barnsey' were pretty close :=).
Your warranty should be fine as loading optimised defaults cannot damage your system. I've never known a system yet that couldn't handle these settings as they are not really as optimised as you might think.
Removing the battery will simply set everything back to safe defaults setting, which normaly means that things will be a little slower than they should be.
You could try going through the best settings manually, but that would require several pages to help you out here and really, if you don't know enough to be messing with bios settings then its probably wiser to leave things as they are until you have some more experience under your belt. Sorry I can't help any more than that.
Take a read at your mainboard manual as that is a good place to start in getting familiar with the various bios options. Have fun.