Your spec will handle DVS 7 fine, 1 gig of ram is plenty!
Remember that songs are loaded into the memory to be played by DVS, reading from memory is much faster than reading direct from a hard disk... so if you are playing 2 songs at 12 mb each, you will only need 24 mb of memory plus whatever mixvibes needs to run.
I can only assume you will be running windows xp on your system due to its spec, if you follow my tutorial on optimising windows xp for use with mixvibes you can have xp run on as low as 69 mb of memory...
viewtopic.php?f=207&t=11532regards,
Bryan