Windows starts up but won't go to log in screen

[drc37]

I was defragmenting the start up process and when it was done it went to start up again and the computer shows Vista loading but then goes to a black screen and not the login screen.
It is a toshiba Satellite A210/215 Series 2gb of ram. I tried system restore to, two days ago, and starting it in safe mode but nothing has helped. When I started it in safe mode it would just go to the black screen again.

[jacalope22]

try Starting it with last known hardware configuration.

[syst3merror]

or boot the vista disc, select repair in the bottom left corner, and then chose "repair startup"

I just covered that section in my Vista Configuration certification training.