My wife just gifted me a MacBook pro which unbeknown to her I quickly ruined and desperately need help to repair! Being a veteran PC user I thought I knew what I was doing...but apparently not. The symptom is that when I try to boot up I just get the apple logo and an eternally spinning cog. I am sure that the problem was created by me when I was trying to set up user accounts. I recall unchecking a box (disable guest account rings a bell but could have been something else) which I thought at the time might have a regrettable outcome. If (like with safe mode on PC) I could get back to that screen I could back track and fix the problem but alas the Mac safe mode does not appear to allow me to do that.To compound the problem, in an effort to repair the OS I managed to get a Snow Leopard cd stock in the D drive which now beeps in tune with the spinning cog.....my wife is now starting to ask questions about the strange beeping noises and why I spend so much time in the shed with my new computer.....any help is appreciated.