No password field on login screen
I'm having a really big problem with my MacBook Pro. I'm trying to log in but I can't. When I power on my laptop, all I see is my user picture on a gray screen. That's it. No password field below, no buttons for switching users, etc. Just my account picture inside a circle. I've tried the following:
- entering my password anyway
- reset the parameter RAM
- tried to do the Apple Hardware test, but it just leads me to the fail login screen
- tried using my Snow Leopard disc (I'm using Lion), but it won't let me change passwords, use Disk Utility (all buttons in the First Aid section are grayed out and the "hdo2" under the hard drive name is grayed out too). Heck, I can't even install back to Snow Leopard since the disc can't find the hard drive present in the Macbook Pro!
Help would be hugely appreciated! I have a lot of important files in the hard drive (most of them are backed up but I wanna make sure) and I don't want to lose them.
Thanks