Regularly Losing Internet Connection: Losing My Mind

Hello Everyone! I have a relatively new Dell, a E1505 T2400 about 10 months old. Using either the Wire or wireless, I connect to the network and access the internet no problem, then I get a prompt when linking or refreshing a page that my browser (happens using any browser) "can't find the server" or "page not found"?? I have to go to Network Connections and disable/ enable or repair and things are fine again- sometimes for hours, sometimes for only a matter of minutes. Then it's back to the disable/ enable thing. It's maddening. Network status claims active network connection, testing the network card I ping and pass, I don't lose addresses or anything I just lose access to the internet. I disengaged my firewall and use the router's, so no conflict. When this occurs, Outlook also can't find server. The other computers in the house have no issues so the issue appears to be me. The problem suddenly showed-up a while back and appears to be getting worse. No settings were touched. I have a DSL line and the router's a Netg FSV318. All the settings are in order - the other three computers (some using wire, some wireless) using it have no problem whatsoever. Again, just me I have constant network connectivity - I checked my pc's card settings and all are fine, and the task mangement network claims the card is operational for both modes. XP 2 pack, Antivirus is Av*st! Full scan, no virus. I stopped Av*st and still had the problem. I have N*rton, but only the basic which I use for the utility programs. I'm stumped. I guess I need to know if this is something hardware related that requires sending it back to get fixed. Oh, and in the short time it's taken me to write this I've had to copy and paste it three times for "server not found -- disable, enable..... ..... Ugh! .....disable, enable .... Ugh!... (repeat ad nausuem).. Sorry for the long post. And Thanks! cheers, (I tried to run the virus check in the safe mode, but the program hangs-up when it hits video drivers. So dunno.)