Sounds like your hard drive is about to go. Backup whatever important data you have and run a hdd diagnostic on it.
Reformatting won't help in this issue. Kinda concerned that someone would put windows ultimate on your lappy. Assuming that is not a legal copy. That or he up-sold you to something you really really didn't need.
*edit* nvm my ultimate comment. Completely overlooked it had vista ultimate on it before. Was most likely an upgrade.
Thanks for the quick post, Thought so its hard drive dying to but how come its working fine on safe mode? anyway could you help me on how to reformat with a cd?