Help! My laptop is stuck on the start up screen!

I have recently updated ubuntu 10.04 and now when I switch my laptop on, it's stuck on the startup screen which is a purple screen with the ubuntu logo. I can access the terminal but when it asks for my password it won't let me type and keeps saying login failed. I have no start disk and I am panicking as I desperately need a piece of information off my laptop. Any help would be hugely appreciated!!!

Terminal and password

"I can access the terminal but when it asks for my password it won't let me type "

As a security measure when you type your password in a Terminal you cannot see it. Just type your password and hit enter.