What's the question for the first screenshot? I see your wireless client connected with 95% signal (apparently it's like right on top of your router

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Can you explain what doesn't work on WAN cable means? Your modem should run into the router's WAN port, and one of the LANs runs to your NIC. If you've got it wired up some other way that's likely the problem.
Also, WEP is only slightly better than unsecured. If you can I would use WPA.
Thanks Cromewell: i have Good news: I was able to figure out this DD-WRT configuration on the Buffalo WHR-HP-G54,and Updated the Firmware from build 13521 to build 21286, and i've set up a Secure WPA2 and you know what All my wireless machines work great and have a very good Wireless signal,i almost screwed everything if i went with Tomato that has no secure we-pa,besides i probably would brick the router.so i'm very stubborn never give up that's lots of work but that pays off.
i bought this Buffalo WHR- router 5 years ago for 60 bucks at Amazon and Flashed DD-WRT firmware,but i could never make it work ,so i put it on my scrap, to tell you the truth i thought i had bricked it,and could never get it to Factory Buffalo Firmware,all this because of lack of understanding English and DD-WRT configurations of Firmware and software,besides i went with the Crappy Verizon DSL and Phone and with Verizon Routers never needed another wireless router,so by necessity i just started to reed and Google about the matter,and at this time i understand a little more about Computers and software and that helped a little bit as so the clues i've got from forums like badcaps forum.
I've resorted last to Buffalo cause i tried to Use these Routers that i also had in my scrap, but could never do a secure Wep or WPA ,Toshiba WRC_1000, Net gear WNR2000,
Belkin F6D4230-4 v1, these old routers only worked ok on my old machines open Secure protection,and i had to shutoff the routers when in use with wireless to avoid worse damage by someone using my Wireless,also these routers open secure only gave me 4gbits out of the 3,