If you're using an Ultrapeer-capable client, disable its ability to become an Ultrapeer. If you're an Ultrapeer (and probably likely if you have a speedy DSL connection - even though you selected "Dial-up"), you become a hub for dozens of other Gnutella clients - you're doing all the hard work for them, including responding to queries for them. If it continues, I recommend selecting another Gnutella client.