I've got about the same setup with one difference.... 2Gb RAM. I added 1GB extra RAM and it makes a world of difference! Everything is a lot faster now. You don't need a new machine, but get more RAM is definitely worth getting.

Artwork and 3DToons items, create the perfect place for you toon and other figures!

http://www.renderosity.com/mod/bcs/index.php?vendor=23722

Due to the childish TOS changes, I'm not allowed to link to my other products outside of Rendo anymore :(

Food for thought.....
https://www.youtube.com/watch?v=pYZw0dfLmLk