wlan driver completely messed up my pc

hi guys,

i have desktop pc with a vista home premium 32-bit os. its been working all good for the last 3 years until yesterday when all hell broke lose as i decided to upgrade my pci wireless network adapter 802.11g to a usb wireless 802.11n. i uninstalled all old network drivers and removed the card from the pci slot. i then installed the drivers for the new usb wireless adapter and plugged it in. apparently the driver (realtek) signature wasnt valid so there were some issues from the very start. anyway, i managed to get it to work and i could enjoy faster internet connection for like 10 minutes, then my computer crashed. when i rebooted it i got the blue screen from hell with the message "bad pool header". i managed to enter windows via pressing f8 in the boot menu and choosing "disable driver signature" but my computer froze everytime when entering windows (most probably when windows tried to load the wlan drivers).

i tried to fix this problem via my recovery dvd but i didnt have a good recovery point. i couldnt do a system restore and startup repair didnt work either. i tried to see if there was a way to get to msconfig via the command prompt so i could disable the wlan to load at the startup, but i cant manage to find it (even tho ive tried various options as described on online forums).

ive tried to uninstall the drivers via command prompt. didnt work. ive tried to remove the files in the folder. didnt work. i have removed the specific wlan drivers via regedit but that didnt work either. ive even tried to fix the registry by copying a regfix via my external harddrive to my desktop pc. still no positive result.

im basically stuck here. i cant go via safe mode as i get the blue screen and when i go via "disable driver signature" windows freezes at startup.

i think the solution to this is to stop the computer loading the wlan drivers at startup in order for me to be able to enter windows and exorcise the whole goddamn thing.

is there anyway anyone can help me, please? any form of support is much appreciated!

cheers
tomas