Lots of information there and well set out, without looking too busy. A nice information site.
I didn't see any Flash there in the Page Source I looked at in Firefox, and it works with no problem in FF4. I also tried it in IE8 and again no problems.
Dreamweaver should work with Vista, but check with the Dreamweaver web site to be sure. Maybe you have Vista 64 bit and Dreamweaver only works on 32 bit systems? You can check that.
But in essence Dreamweaver is only an HTML editor and browser emulator, so if the site works in any browser, it should work in DW. In addition, if DW only crashes after a few minutes that might indicate some other problem with the system. Any error messages on the crash, or visible symptoms? Does DW crash on other html files?