Local access but not Internet access

Hi, i have a Vostro1400 and have had it for 4 monts now, but recently the wireless internet seems to be playing up. It connects to the internet sometimes for a little while and then off again. Ive read most of the posts in these forums and tried all sorts from restartin the wireless reinstalling repairing and disabling and elabing loads of other things. However i still get this problem. Im runnin on WindowVista 2gb ram 2 ghz etc top spec. the only problem i have is the Internet connection. Even in the network and sharing folder it shows my wifeless is connected to the computer at home and all works well...but it just isnt connecting to the internet. Could it be the wireless card problem in the lap top? My computer at home where my wireless is connected works fine and all the lights light up on my broadband virgin connection.

Anyone experience similar problems?

Im getting enoyed with this intermittent problem of connecting then not connecting. Thank you.