|A Curser is someone who swears or curses - I think you mean cursor ;)|
From Safe Mode look in Device Manager and see if there any errors showing. If there are, let us know all about them and we can probably help you. Often a computer that only boots is Safe Mode has some sort of driver issue (because Safe Mode loads with minimal drivers).
It still could be a virus but I think it best do the above as a very first check. If no error is showing then follow the advice already given in #2.
If none of this helps then type msconfig in Search (hit Enter key) then click on what it finds. Look in the Startup tab and see if temporarily un-checking any item cures the symptoms. If so we can look more closely into that item.
Always pop back and let us know the outcome - thanks