Sounds like an IP clash. Make sure nothing is on a fixed IP address so that the router can assgn addresses.
On the desktop check TCP/IP Properties.
Start, Connect To, Connection, Properties, Scroll Down TCP/IP and highlight, click Properties and check that Obtain DNS and IP address automatically are enabled.
OK sorry it took me a while to get back to this but medic school has put this on the back burner. If you are talking about the start menu I can't find connect to options. I'm still unclear as to how to check the TCP/IP settings. I know the router itself used dynamic addresses. Sorry for the nub question.