I had a little trouble as well when I upgraded to 2.4.18-5 from 2.4.18-3. Normally, using the untared drivers folders works fine, (or used to).
I found that the install folders get somewhat "messed up" after an installation. So the solution for me was to upgrade the kernel and the kernel-source, erase the old nvidia folders (kernel and GLX) and untar the original archives again. 'make install' and after afew tweaks (the driver didn't load automatically) everythin' works again.
Use the source, Tux.