WI Fi help

OK just got the Bionic last week, so far other than battery issues I'm pleased.
Here is my problem.
I have a linksys wireless router, connected to this router is a wireless access point so I have coverage all over the shop yard.
I would rather use wi-fi when downloading or updating. So I also have a toggle widget to turn the wi-fi on and off. To save battery.
When I enable wi-fi it goes through obtaining an ip address, authenticating etc..and then disconnects then goes to the other network and tries connecting there. It just goes back and forth and never connects or shows an icon that wi-fi is on and being used.
I want to specify which network to use a or b
Have notification of wi-fi in use and does anyone know why it sees the networks, authenticates but doesn't connect?