cant connect iphone 4s and ipad to wifi after ios 6 update

i updated my iphone 4s and ipad to ios6, and now they wont connect to home wifi.  my iphone 4s does connect to wifi at work, so i know it can work, and our iphone 4 (also updated to ios6) connects to home wifi, so i know home wifi works.

already changed all router settings to apple's recommendations, that didnt fix it

if i restore factory defaults to the router, then, and only then, will it connect...but that's no good either... i cant even change the name of the network, and instantly it stops working. have a belkin n600 router

any ideas?