There is a text file included with the Windows SETI@home client, the other clients may also include a similar readme file. It can be found in the SETI client directory. In this text file you will find more detailed information regarding the SETI@home project and the client.
The people that brought you SETI@Home have an excellent FAQ that can be found here.
If you want to know what all the graphical information means when the screensaver is running, take a look.
JSetiTracker, an all Java front-end.
Team AnandTech @ SETI stats page. Show your support of Team AnandTech @ SETI and use this link in your Signature file.
SETI@home main page You can find a lot of information and statistics at the SETI@home homepage. There are plenty of FAQs to explain every bit of the SETI@home project and clients, like The official SETI@home FAQ .