I have a sony vaio windows 7 laptop and I restarted my modem and now I can't connect to the internet. When I try to connect to my router it says I have limited access. My other computer connects to the internet and works fine. Any help would be appreciated.

How do you know it has an invalid IP Address?

What address did you laptop receive?
RUN > CMD >type ipconfig

Try disabling IPv6 on your wireless network connection properties. Control Panel > Network and Sharing Center > Change Adapter Settings > right-click on Wireless Connection > Properties > under the list of properties the connection uses uncheck TCP/IP v6

Have you updated your routers firmware?
Try using a static IP (a manually assigned IP)