Well, I'd get a surge protector (Power strip w/ fuse) first as it's cheaper, this might be all you need (and a new CMOS battery if that is bad, please test with another, you can cut the power yourself for testing via PSU switch)

No, you can't edit the default values, and you should start with optimized not safe (Just saying since you mentioned safe). They are part of the BIOS itself, so stored in the BIOS chip and programming, you can't change them.