Anyone have any suggestions how I can fix the problem that when I load, such as going into any dungeons or caves, it causes Skyrim to be "not responding"? I also can not use any carriages or Fast Travel either.

It used to do it every time I loaded into a city also but ever since i downloaded "Open Cities" mod I can go into towns & buildings in towns fine.

Everything worked perfect before 1.7 patch which auto downloaded. I have re-installed completely already. I have taken off all mods but it doesn't change anything. I started a brand new game. I don't have any sound mods. I have plenty of RAM. I got a great graphics card where I can play up to "Ultra" setting but I set it down to "High". I turned off Autoaliasing to see if that would help. I got a new .ini file from Steam. I don't have any "blood" mods. I don't have the "Wars" mod.

I have skyrim loading first, then update, then Dawnguard, then everything else via Nexus.

Any suggestions what to try next?? I am stumped!