Computer won't start!

[Jodiel123]

My computer won't load!

I try to start normally, it gets to the used log in then freezes when loading, everytime I start it want to do a disk scan, if I do this it still doesn't go any further than log in. When I try open in safe mode it freezes and doesn't open. I have tried repair my computer from
Pressing f8, it says the backups are corrupt so can't restore from earlier date, I've done the start up repair which completed, when restarted computer it still wouldn't go any further than log in.
Please can anyone help??

Although i am fairly confident on computer I don't do technical words as
You can tell!!

And I have a Sony vaio running windows vista

Thanks in advance

[Jodiel123]

I have just managed to log in, it came back saying access it denied! Now says other credentials below, when I click this it shows my user name then other user and asks for user name an password, I havnt put any other users on!