vista startup problem HELP!!

(in safe mode)ok i looked thru the forums and google and could not find my problem so i am posting it sorry if this is a double post. 99% of the time when i boot up my computer all the lights and stuff turn on but my screen doesnt it stays like that for 10 seconds and turns off and starts up by it self again so i have to hold the power button to get it to stop and the 1% of the time when it does boot it gets to the screen where it says safe mode with networking etc and start windows normally if t choose the start windows normally it loads and when it reaches the profile choosing screen all it shows is static (like the static on a tv) so all the pixels and the logo and everything is messed up and i acnt see what im doing i i tried restoring as far back as possible but no luck and when i bought my computer it came with no recovery disc so i have no way of resotring it back to factory defaults any advice or help would be great

Yikes!
So you can only work from safe mode, correct?
Please fill out your system specs in the lower left corner.
Look at device manager to see if you have any question marks or exclamation marks. What do you see?