30 seconds is pretty extreme. Usually it's a half-second pause and maybe 2 seconds when you come close to a large group of NPCs and it has to run the scripts for all of them.
Any idea what your system is doing during this 30s wait? Is your hard drive light going crazy? If so, maybe there's an issue with your page file and the system is swapping back and forth between memory and disk excessively. Check your page file settings (usually, "let windows handle it all" is just fine) and that you have some space free on the drive that holds your page file.
Another thing to try is disable your anti-virus before playing the game to see if it makes a difference. Sometimes anti-virus will scan large files every time they are accessed and cause long wait times.
This is my music computer, so I keep it off the internet and antivirus free to maximize my resources.
When I open the task manager while it's doing this, one of the cores is being fully utilized. I'm running this on an SSD, and just read that I should turn off indexing on that drive. I put the indexing on a separate HDD, and the load time is now about 10 seconds.