Laptop Won't Boot up?

-I Have a Dell Studio 17, about 2 years old. It came with Windows Vista and a free upgrade to Windows 7, which I upgraded to.



Now recently, I tried to play a song on iTunes, so iTunes froze and I closed it (it wasn't responding), then I tried opening it again and it froze again. So, I turned of my computer, thinking to restart and fix it.



But now, when I try to turn it on it asks if I want to start normally or go into some sort of repair mode. I tried starting normally, and it takes me to the loading Microsoft screen, only the microsoft flag is missing and it gets frozen. (if i leave it long enough it takes me to he repair thing anyways)



When I try going to the repair stage, it takes me to my welcome screen (only without saying anything) and I just have my cursor. I left it on for a hew hours, and it started scanning my system and trying to fix things, but then I left it like that overnight and when I woke up it was back on a plain welcome screen, stuck again.



I tried calling support and they decided (in about 30 seconds) that it was a virus and if I even wanted furhter support it would be 139 dollars per call or like 250 dollars for permanent, with no gaurantee the problem would be fixed.



I just want to know if there's any way I can fix this without spending a fortune. It should be noted that i CANNOT in any way get onto my computer to do anything past like press f12 for boot menu and such.



Thanks