If NVdriver is loaded, then your driver update didn't finish successfully. The kernel module is no longer named NVdriver in drivers 4191, 4349, or 4363; it's now named just "nvidia"(.o, but the .o should be ignored in modprobe or insmod commands) instead.
Try to modprobe nvidia (as root, obviously) -- if you get a module not found error, then rerun the installer, and make sure you check the nvidia-installer.log when you're done. The installer should delete the old NVdriver kernel module for you, so it almost sounds like it didn't even start up correctly.
It says 2.4.17 in the log file because that's the build operating system, not the version it's running under. It just means that whoever (at Debian) built the XFree86 package, was using kernel 2.4.17 at the time -- it shouldn't matter.