It's good to be that careful...

Sorry, I just have the Pro CD and there I'll be asked to install (F3)(?) or run the
recovery console (not "repair" ) by pressing 'R'. Not to confuse with 'R' for "repair
install, which should appear one step later, after choosing "install XP". (Don't know exactly, I don't use that stuff much)
Another option would be a "Bart PE" image or a "Knoppix" Linux Live CD (
http://www.knoppix.org - download an image and burn it). This boots a complete Linux operating system from CD. After some reading, you will be able to access your NTFS drives and delete the file safely. The idea with all this is: To boot something from CD that lets you access your files, since you cannot boot up your obstinate XP system. BTW this is odd since the other users that reported problems with vsdatant.sys could at least boot into Safe Mode. Chances are that all this won't help then...