Win7 Wireless connection drops

I have an old IBM Thinkpad T42p with Intel(R) PRO/Wireless LAN 2100 3B Mini PCI Adapter. Yes, it is in 801.11b, very old. But since it can copy files in 180KB/second, why should I replace it?

The router is Linksys WRT54G with original firmware. The computer can dual boot into Ubuntu 10.4, and the connection is very stable. But when it is boot into Win 7, the connection keeps dropping.

I googled "Win7 wireless drops" and literally tried all solutions but failed. The last method that works is:
In the connection property, uncheck QoS, File and Printer Sharing, IPv6, Link-Layer Driver and Responder (I have no idea what the last 2 are):

Then the connection is great! As I mentioned at the very beginning, it is copying files in the speed of 180KB/second now!

I don't know which one of the settings (QoS, File and Printer Sharing, IPv6, Link-Layer Driver and Responder) did the trick, but as long as the network is good, I'm happy. If you have the same problem, try it.