I thought this was worthy of placing here in hopes that it might be of use. A while ago we deployed an Acer TabletPC with built in wireless and had nothing but problems connecting to the network. We seemed to browse fine, but when it came to sending any data (such as printing) it would fail. The soultion turned out to be creating an MTU entry for the wireless interface with a value of 1472. Info on adding this entry can be found at microsoft.com
Hopefully this helps somebody solve the problem more quickly than we did.
UPDATE: Originally I had thought this problem we encountered seemed to be limited to the Acer product but it would seem that others have it as well. My Toshiba M200 just wasn't right when running wireless. Even some web pages, especially Microsoft.com had real problems trying to load. The above fix of the MTU setting has made a huge difference. I hope to do some more testing, but if you have problems, create and MTU entry for the interface as described equalling 1472.