JRV, I suppose it wouldn't hurt to try SQL 2000, if you happen to have a license to run it (or a remote SQL environment already up and running that you can dip onto). With the hardware, you are very much underutilizing it as a BES (depending on your user base, considering the DC aspect). There are stories of people who moved to SQL 2000 from MSDE 2000 and experienced beaucoup increases in performance.
In the beginning the Universe was created. This has made a lot of people very angry and is widely regarded as a bad move.