restore point & external drive

Hello! i have a serious problem...

i was uninstalling an antivirus program, which made windows xp (sp3) restart itself.
by doing so windows made a restore point. during the boot-up windows stuck to a black screen and i assumed it's because BIOS messed up the order of my boot-hdds, so i quickly disconnected the external USB harddrive (which i also assumed was listed as the first boot-hdd). the boot-up then continued (i didnt need to restart, so my previous assumptions were right) and windows started normally. but when i tried to access my external drive it gave me an error

" J:\ not accessible. the disk structure is corrupt and unreadable. "

the disk was only holding back-up data (files) and was using NTFS. in the disk manager it now says RAW.

what can i do to get NTFS back on my external harddrive without loosing the files?

btw, restoring prior to the uninstall gives me the following msg

"changes made to drive J:\ cannot be reversed because the drive was either excluded from System restore monitoring, or was turned off, or removed. "

please help

It looks like something has messed up the drive's File Allocation Tables or Partitioning. There are data recovery programs you can get that will, hopefully, reconstruct the damage to the filesystem... but you will only get back any data that was not overwritten during whatever crash went on.... Best I can recommend is to hit google, try several DR packages, you may get lucky on one of them. However, when a drive says RAW in disk manager, it usually means the partition table is gone and that's not good news...