Windows Vista

I just downloaded and installed Windows Vista, and it runs very..strangely. It lags every two seconds, and appears to be pretty slow..perhaps its my PC?

AMD Sempron 3000+ 2.0ghz
1GB RAM
GeForce FX 5500 256MB AGP 8x

Not really sure what else would be useful..

Help me out. :(

This just came up on digg:

http://digg.com/tech_news/Windows_Vista_Beta_2_Plagued_by_Bugs
http://www.toptechnews.com/story.xhtml?story_id=1110083YRM69

700 MB memory usage (in Beta 2, 1 GB before) without doing much, that could be the reason.