Vista - plz plz help...dis problem drives me crazy

hi!!!
config:dell wireless 1395 WLAN mini card

well when i try to connect to internet (we have well working wi-fi connection over here) it takes long time,internet page is not displayed .it says waiting for this-this site for virtually very long time,where the same adjacent lap can connect within fraction of seconds,it never says unable to connect internet.interestingly if i restart lap then it connects quite normally,seems like connection goes to saturation with time.i can guaranty that no problem is with wi-fi network,acess is always shown local & internet.LAN works normally.
i have installed latest WLAN card driver,still problem remains & performed tests available to check hardware & network problems which shows no fault was found
sometimes half the site loads & half not....it takes long duration of "redirection"...in device manager out of 18,4adapters were marked namely
Microsoft 6to4 adapter #2
Microsoft 6to4 adapter #3
Microsoft 6to4 adapter #4
Microsoft 6to4 adapter #5
i checked dere solution online but in vain.....
i have network meter in sidebar which shows zero internet signal with some LAN signal when net does not work... but other computer can operate at the same time...after restarting everything becomes all right....no proper restore point available.
PLZ Guide..
Aharnish
INDIA!!!