Netgear wireless router works ok wired, but..

Hello, I have a Netgear CG814 wireless router with wpa-personal security key hooked up thru an ARRIS modem on comcast hi-speed internet. Everything was fine, then my service got turned off....got it back on, now i have two computers with the exact same problem: wired to the router, everything is perfect... but either computer connected wirelessly will not load some websites. both computers are laptops on windows vista, one dell vista basic, one acer vista premium. Both using Internet Explorer.... Wirelessly, Google.com is ok, comcast.com is ok, eBay.com wont work. facebook wont work, aol.com either, etc. etc.... some sites are fine, some never load. it's always the same sites that are ok, and the same that wont load. but wired to the router, both computers are fine- all sites work. i dont get any error messages, all i see is the progress bar just stop halfway and nothing ever pops up on the webpage, just a blank page.. I was on the phone with comcast for 2 hours, resetting modems, ipconfig'ing, flushing dns, nothing helped. Borrowed a friend's laptop on windows xp/int.explorer...same thing...wired is fine, wireless same sites no good.HELP!!!!