Which OS and did you move to at least WPA?
For some reason as soon my roommate installed his Roku box I have been having IP conflicts on my laptop, and my laptop alone.
I cant figure out how to get them to work together, even after releasing and renewing my ip.
I have also made sure that my DHCP is enabled.
I am running two routers- one that has a modded DD-WRT, but I dont think thats an issue..