Ubuntu 10.10 Login

I have recently installed Ubuntu 10.10 on my computer after previously having Windows XP. After installed it it seemed to work until I restarted my computer. The first 6 or 7 times I restarted my computer it would just load with desktop background and an icon of the install disc which was still in the drive. Now it starts loading to the login screen and when I type in the correct password it will flash to the correct desktop for about 5 seconds then proceed right back to the login screen. I am very new to Ubuntu and Linux so you might have to dumb down your responses. I have done some search with some people making suggestions of pressing Ctrl+Alt+F2. When I do this my screen goes black and nothing happens. When I try to restart my computer from the login screen the screen goes black and the caps lock and scroll lock lights on my keyboard flash. Anyone have any suggestions?