You're better off looking at
http://www.microsoft.com/sql/techin...ing/ChoosEd.doc
for actual information, but I'll throw you a bone...
SQL Server Enterprise Ed : all the bells and whistles, can use as many processors and as much memory as your operating system can support, has all the analysis features built-in. Consider this a cadillac, cus it's expensive, too.
SQL Server Developers Ed: Can do anything Enterprise Ed can do, but you can only use it for testing/development. It's not legal to use in a production environment (if your business runs on it/needs it, it's production).
SQL Server Standard Ed: This one's more like a family sedan, with support up to 4 processors and 2GB of RAM, no data analysis services.
SQL Server Personal Ed: wimpy, 2 procs max, has a transaction governor that limits you to 5 concurrent transactions. Can be installed on win98. This one's a Celica.
SQL Server Evaluation: Like the name says, you have 120 days to figure out if the server's for you.
Desktop Edition: No client tools, meant for embedded use. All the features of personal edition. I've found it somewhat hard to install. Like a celica with no windshield/doors.
Hope this helps,
Steve