If you do a scan for wireless networks in your area does yours indicate WEP or WPA enabled ?
Are you sure you're actually connecting to your router ? Lots of people leave the router SSID on default (usually the manufacturer's name) so if you have a Netgear and so does your neighbour you may be barking up the wrong tree.
The solution to all these things may lie within the usually unread pages of the router manual.
I recently purchased a USB Network adapter for my Dell Dimension 2350. It is branded "EDUP" and I got it on eBay. The disc that came with it was of no use, but I did manage to get it installed on my computer. The problem is that when I go and try to connect to my wireless network (using a Motorola SurfBoard Gateway SBG900) my network is recognized through the Wireless Network Configuration tool that Windows uses, but it won't ever connect.
I'm using Windows XP with all the latest Service Packs, 1 GB RAM, basic set up.
Thanks in advance.