DNS error

hi, im currently at my grandparents house trying to setup my ps3 to the internet. They dont have a router so i brought the one i use from home. They have a Motorola SBV5220 Surfboard Cable Modem and the router im trying to use is a Netgear WGR614 v7 wireless router. For the past 3 days ive been trying to re-configure my router to their internet connection and i am having numerous issues. I re-configured it to their IP address and DNS addresses and everything. When i set everything up, the wireless switch on the router is green, the internet switch is green, the lan switch that goes to my ps3 is green, but the lan switch that goes from the router to the back of the computer is orange and there is no internet connection on the computer eventho the internet switch is green. And when i go to set up the network connection on my ps3 it reads the IP address but i get the DNS error everytime. ive tried making it wireless but that doesn't work either. I've disabled the media server connection, put in the DNS address 208.67.222.222 and 208.67.220.20 and that neither of those work either...ive rebooted the cable modem and the router several times each and no luck. Im guessing i somehow have to set all of this up and maintain and internet connection on the computer as well for it to read it but i have no idea how to manage that. I'm also trying to make it so that i can just reset their internet setup to the way it was when i leave to go home within the next week or two so im not trying to change anything thats not reversable...i just bought socom confrontation wednesday and really dont feel like waiting a few weeks to get to play it...anybody have any ideas? sorry this things so long but over the past few days ive tried a million things and nothings working.

Thanks