Have I made things worse?

My (mis) settings on the original operating systems blinded me when I messed with the RADEON MOBILITY Multi-Monitor. How do I see the light again?

I loaded XP Pro again, so I have two copies of the same OS beside one another - NTFS, no partition. What is the fastest way to get to the other OS to change the settings? Can I retrieve my files and applications so I can back them up and reformat the HDD and start fresh?

Notes on original problem:

ATI MOBILITY RADEON X600 issue?
Dell Latitude D810 DVD viewing on Sony LCD TV via S-VHS cable
Laptop display no longer works once Windows XP Professional is loaded

I hooked my Dell Latitude D810 to the monitor to my Sony TV via S-VHS cable.

I watched a DVD from the laptop drive on my laptop monitor and the TV monitor full screen (they were not split screen images).

It worked great until I decided to try and “fine tune” the image dimensions on the TV.

CONTROL PANEL > DISPLAY > SETTINGS > SCREEN RESOLUTION & DISPLAY

I was playing with 1 and 2 boxes in the window DRAG THE MONITOR ICONS TO MATCH THE PHYSICAL ARRANGEMENT OF YOUR MONITOR.

I am not sure in what order the events unfolded, but the TV monitor suddenly showed only the wallpaper image on screen, but the laptop still had desktop items and task bar on with the wallpaper image.

In the DISPLAY field in SETTINGS, I was scrolling between 1. (Multiple Monitors) on ATI…
and
2. (Multiple Monitors) on ATI…

I may have messed up with the settings in the ADVANCED tab too.

My laptop display no longer works once I am in Windows XP Professional.

F8 and F12 allowed me to run diagnostics (all passed) and a safe mode start that also loses the display once XP Pro is loaded.

Once XP Pro is loaded, I can hear the laptop accepting my password entry with its cute little “beep”

It sounds like a pop-up block shortly thereafter – not sure that is relevant.

Once, I successfully used the mouse pad to right click in the far lower left of the screen, apparently opening the START menu and SHUT DOWN, otherwise, it was the unplug or remove the battery method.

Dell Tech Support walked me through booting my system from the Microsoft XP Professional Installation Disc, but it failed to reactivate my screen.

I have tried enabling anything to do with video cards, or lack of, from F8, but to no avail.

When I increase and decrease the brightness, I can see the screen glow ebb and flow.

Dell Tech Support suggests I go to Best Buy to have them back up my hard drive, and then erase the hard disc (“something may be corrupted”).

I am not sure that will solve the problem.

I attached my laptop to another laptop with the S-VHS cable, and it split the display on the other laptop, but mine stayed black.

I attached my laptop to 2 other monitors, and another TV, and I got nothing!

I have recently added some extremely important files for work that have not been completely backed up, and would like to feel secure about their continued existence while I play the less-than-omniscient God of the keyboard and mouse pad.

I would love to understand what happened, and get it fixed ASAP.