Windows freeze at start after installation of new nvidia drivers

Welcome to Seven Forums. Obviously the new driver isn't playing nice with your card.
If you can boot into safe mode I would suggest to, and then remove the new driver>reboot and re-install the older driver.

You might even want to try different drivers and possibly find one that works best with your card. heres an older one you might want to try http://downloads.guru3d.com/Forcewar...load-2525.html

It has been suggested to use a program like Driver Sweeper after you un-install the old driver to remove any remnants of the driver you have just un-installed before installing a new one.
http://downloads.guru3d.com/Guru3D--...up)_d1655.html

Sometimes they make changes in the new drivers that don't seem to work well with certain video cards. Especialy older ones or medium cards. Their focus is more on the newer GTX series cards, and sometimes can creste unforscene problems with other series cards
.
I would have to compare the release notes on the new driver to even try and guess at what might be causing the issue. You just never know.
It's kinds like back to the old saying if it ain't broke don't fix it.

I realize you were probably hoping for some increase in performance with the new driver only to find out for some reason it's causing you problems.
Sorry but that's about all I can think of.

I would also like to add that whenever I download a new driver or app I like to create a restore point.
That way once I have removed the driver/app I can easily restore my system to it's previous state.
Maybe someone else might have a better explanation for you, so we'll see.Fabe