Expert Help in Wireless Networking Needed, Multiple Devices!

Ok I am trying to have 3 to 4 different wireless devices operating, not at the same time but I want them to work when needed. Here is a list of what I have in the household:

Netgear WNDR3300 Router/wireless dual band-N
Linksys WGA600N Wireless-N gaming adapter
LG Network Blu-Ray Home Theater system, Model:LHB953
LG Internet Connectable/Wi-Fi Built-in Blu-Ray Disc Player, Model:BD570
XBox 360 Pro 60 Gig Hard drive, no wi-fi built in, older one, white
Desktop computer: Compaq Presario SR2010NX, Windows XP, Service pack 3 Home Edition Version 2002

I have 5M dsl with Centurylink. In my room I have my desktop computer, my xbox 360, and my LG LHB953 Blu ray home theater system which i have the Linksys WGA600N Wireless -N gaming adapter connected to. I have my Netgear WNDR3300 Dual band Wireless-N router currently in the same room with my desktop hard wired in one of the ports on the router. Everything works fine except for the fact that i bought my parents an LG Wi-Fi built in Blu-ray player model:BD570. My room is upstairs and on the opposite side of the house. I recently moved the router and dsl modem to the other end of the house in a room directly above the living room where the wi-fi player is located. Ok the wi-fi player downstairs now picks up a great signal, but now I have to run a 50 foot ethernet cable from one side upstairs to my room to connect to anything. I have to hardwire the computer or the xbox 360, nothing in my room will connect wireless with the router moved down the hall. It's about 50 feet give or take from one end of the house to the other, and with the living room being on the opposite end and downstairs that might be about 150 feet, give or take. I've been looking at a netgear gigabit router that does 600mbps but I don't want to blow $150 if it doesn't solve the issue. I just feel totally lost here and it doesn't seem like any of my friends that went to the community college here decided to take any courses in wireless networking. I am in dire need of some advice and help. Please, somebody....

 

I'd get a linksys or netgear router that will run ddwrt & make a wireless bridge. I sure it could be done with other hardware but I have made several with the ddwrt ios routers & it is easy. It would be cheaper too.

http://www.dd-wrt.com/wiki/index.php/Installation

http://www.myopenrouter.com/

How to bridge
http://www.dd-wrt.com/wiki/index.php/Wireless_Bridge

 

Thank you for your quick replay but something odd to me happened. I moved the modem and the router back into my room and hardwired the xbox 360 and the desktop to the router. So i have my blu ray surround sound system connected to a wireless adapter and my parents wi-fi blu ray player downstairs at the other end of the house seems to work fine at the same time as I watch netflix. I don't know how to explain it because it would not work when I bought them the wi-fi blu ray player for christmas. But everything seems to work at the same time, my parents wi-fi player runs the 2.4ghz and mine runs the 5.0ghz.