Not sure ... how fast is your computer ? I try booting in safe mode on my school computers, yet the only thing that i can get for quite a long time is the file destinations of the files being loaded ...
if you are having problems going into safe mode then something is probably very wrong with your operating system.. thats why he said reformat, cause something like that can only be cured with a fresh install.. and I thought it was F5.. maybe i'm wrong.