Trouble connecting to wireless network

I'm trying to connect an old linksys adapter to an old 2wire gateway on a fairly old sony pc. I recently lost my laptop, to the evil monster called faulty parts, so my last resort to have a internet connected pc is an old sony pc and an old wireless adapter (from my old pc which no longer lives.

EDIT: I've manged to connect to the network, and I'm receiving about 10% of the sent packages, even though the signal strength is at 90%. I've tried the "repair" feature that comes with xp home, but it won't clear the DNS. I've also tried the command prompt ipconfig/flushdns but it still won't do it. Does anyone know any other methods to flush a DNS cache?