Stable is rather arcaic... It comes with things like gnome 1.4 and kde 2... It doesn't really make a good workstation. And in Debian terms... stable means ROCK solid. and I do mean Rock Solid...stable is a hoss.
Testing makes a much better workstation... It stays fairly up-to-date, and it's as stable as you really would ever need. Using the testing distribution is generally recommended. Here's a link to dl testing: http://ftp.acc.umu.se/pub/cd-images/debian-weekly/
I personally install debian off the net. If you have a broadband connection, I would highly recommend this approach... For one thing, you only have to download 1 cd, which is only used for the base system installation. Also, you stay up-to-date, and you have access to all the software in their repository without having to download 14 ISOs...ick. Net install is the way to go.