Blank Monitor Error during Multiple Display setup

HTPC Newbie. More than one error at the same time...
While setting up Multiple display on Video card, some how I selected an option that has left my Monitor blank (even when re-booted), and the second display - a TV - not working / no visible output i.e., blank/black. I cannot see ANYTHING on either Monitor (CRT) or TV. How can I get the visual back (so Ican fix my errors/continue)?

Config: Windows XP H, Asus P4P800S-E Dul; Intel 2.8G 800 fsb; 2G RAM; WinTV 150; GeForce Nvidia 5500; internet via 801.11g; Comp Monitor -5 yr old 20" Sony CRT w analogue 15 pin; TV -Sony 20" Wega with component input (supports PAL and NSTC with VCXR built -n).

The Comp monito was via teh 15 pin, and the TV was to be connected via the Nvidia DVI connection using a component connector - which I am still trying to -or was - to make work.

I have reviewed these postings (one year back) and have not seen any similiar issue. I am confident (NOW after reading Nvidia support pages) that if I had waited a few more seconds, the Nvidia it would have revered to previous settings. I have also not found a solution at Nvidia.