As I, and Scott, suggested, you can help Tech Support by monitoring your server's load from the shell. If, when they check, things are running fine, it's hard for them to get overly concerned.
Right now, both the sites in your sig are loading fine for me, but they were slow earlier. It would help you,and Tech Support, to know what the server loads were during those "slow" times as well as the "faster" times.
You also did not indicate whether or not you are using Wp-cache, and that can be important.
Lensman also correctly points out that you have a good deal of "latency load" built into your site with all you have going on "off site" on a page load (Google Analytics, site stats, etc.). Everytime you go "offsite" to "get" something, you intoduce another whole set of variable into the "what could be making my site slow" equation.
Again, you should look seriously at what, and how many, WP Plugins you are running. They can bring a site to it's knees.
Now that you have some of the techies "stirred up" enough to offer some constructive suggestions, following through on some of the suggestions you have been given might help you help yourself, and might help DreamHost help you! [smiled]