does this happens only with the WAG200G router?have u tried connecting to other APs?

try to connect to your friend's, workplace, or public (eg starbucks) with different network security (WEP, WPA-PSK, PEAP-MSCHAP2)..

if the same problem still persists, u might have a faulty unit..like me..

my problem is the N900 sometimes connect,sometimes doesn't, sometimes wouldn't even detect any connections (wifi+gprs), sometimes connects flawlessly...tried with other APs, still the same..went to Nokia Service Centre, they tested and concluded that the board is faulty..so, they'll change the whole motherboard..