I get to about 5%, then it just freezes. Any ideas?

5% what? Loading FalloutNV.esm?

Yes, just loading the main esm. gets to about 5%, and stops responding.

does it crash or freeze? You seem to contradict yourself there.

If it crashes, does it give an error?

If it just freezes, have you tried just letting it run? Ive noticed mine do that and it still loads.

Just because a program says its not responding, does not mean its having problems. All it means is that the program is too busy to tell windows "Yes, I am still running".

Every time I load the GECK it gets to about 4% stalls and says (not responding) but if I let it sit for a minute or so it finishes loading. I'd guess that you are having the same thing happen.