Windows 7 on Dell XPS L401X Blue Screened, Startup Repair not loading

I am trying to sell my Dell XPS L401X (XPS 14) that I bought in December of 2010 but I have encountered a serious problem with it. I loaded the computer from factory settings as it had blue screen and refused to start up without startup repair and dell datasafe backup or w/e that program is called. I loaded it up, installed Google Chrome, cleared my history on IE, downloaded MSE, the latest nvidia drivers and java 7 64 and deleted all those and emptied the recycle bin once done installing those. I shut down the computer to install updates and get a blue screen as soon as it passes the startup screen. Every time I attempt to launch using startup repair it just opens up another window with a black screen and the option of startup repair and normal repair, never actually going to startup repair, just continually refreshing every time I select startup repair. Please help I need a permanent fix ASAP as I don't want my buyer to experience these issues and send it back.

Proceed through the steps in Troubleshooting Windows 7 Failure to Boot and see if that resolves the problem.

You may also consider Clean Reinstall - Factory OEM Windows 7 since the system is no longer under warranty anyway. Just make sure you can read the key on the sticker prior to doing those steps.