Couple of things-
Yes I have wireless working with an MA111-older 802.11b I found at CompUSA.
I have WEP enabled-why? Because it's enabled on my wireless network for some semblance of security anyway.
The point being, if your network is WEP enabled, the Roku must be, if it's not, the Roku must not. They gots to be the same
System information NEVER shows I have an IP address-ignore it with the beta.
The critical factor re: USB wireless is that the port supports only USB1.1. Finding an adapter is a pain in the butt, and doesn't povide much bandwidth.
There is no D-Link DW-111-I'm guessing you mean the DWL122.
Your no DHCP address is the problem-Verify your WAP54G setting for SSID-WEP-Network Name etc are identical to the 122.
If you get shares showing up in the Setup>NetworkShares on the Roku, you need to put a check next to the ones you want to "mount"