XP & TV Tuner Problem!!! Please help

I am using Windows Vista Extreme Edition (a modded version of Windows vista ultimate edition). I recently got a Pixelview PV 3000 but vista does'nt recognise it.

Pixelview has not released its drivers.

So I tried installing xp on my primary hard disk all went well until the reboot. It displayed a message "Error loading operating system". Neither I was able to install xp nor I was able to boot into my previous os. Moreover one of my partition was also deleted. It now shows up as free space in Disk Manager.

So I installed Vista in my secondary hard disk but when I tried installing XP again on my primary harddisk (secondary being disconnected). It gave the same message and my another partition was deleted. I tried fixboot command and it did not help.

Please help me so that I can atleast get my tv tuner running or if I could make xp and vista dual boot...

Please tell a method to recover data from the deleted drives.
I've tried all reputed softwares for that but they dont recognise that deleted partition

Regards...
Saif

Thanks