Attaching wireless router to existing one?

I am going to buy a new wireless router because mine sucks for HD gaming and video streaming. I have a wireless router in one room and an ethernet cable goes from that to another room. Is attaching the new router to the other end of the ethernet cable a bad idea? I would like to create two wireless networks. One for my laptop and the one on the ethernet cable is the one for HD video stream. It is optimized for HD. Its the Vizio Router. The router in the other room is the Linksys WRT54GS.