Linksys WRT54G2 V1 issues

Hello,
I have had this Linksys router for a bout a year now, and have dealt with the issue up until now- but I'm getting fed up. I have had this router in two seperate houses and in both cases i can only connect (get reception) with my laptop or game console if it is in the same room and only a few feet away from the router. Put a door or heaven forbid a wall in between and you get absolutely no reception. I had, and a friend still has, the older version of this router and has had no problems being upstairs, downstairs even outside on the deck....I have connected to neighbors networks who are hundreds of feet away with my laptop but can't get onto my own just thirty feet from the stinking router!! HELP!!