Well your site is extremely slow in all aspects from what I am seeing. I am on cable access and I probally have speed at your site reminescent of the old days of 24K
I would do a optimize on all your mysql tables. Your may need to run a more detailed myisamchk if you have not ran on the tables just to uncover any issues and repair it.
I think you may want to see how much bandwidth your using and your user load. You may need to upgrade your plan or server.
You can turn some options off to save queries. Probally the best is turn off WHO'S ONLINE