Can't connect to new wireless network on iPhone4 w/iOS5

I have an iPhone 4 and upgraded to iOS5. Since that upgrade, my 3G connection has been unreliable. Sometimes it works fine, sometimes it disappears, sometimes it says I'm connected and just hangs (never gets to opening web pages or sending or receiving mail or doing anything else requiring a data connection). I tried a variety of things to fix this, trying to avoid any settings resets, and the only thing that made a difference was turning off the phone and turning it on again.

This problem happened many times a day, which was not sustainable, so I called my mobile phone network to ask them what to do. My network tech support said I should reset all network settings and that should hopefully fix the problem, so I did that. Now I've ended up with an even bigger problem! Reseting all network settings wiped out all my stored wifi networks and passwords, so I had to reconnect to my home wireless network anew (fine).

Here is the problem, though:

The network appears in the choose list, so I choose it and enter the correct password (WEP), and push "join". A spinning wheel appears beside the network name and the phone never connects to the network. If I turn off cellular data, I appear to be connected to the network at full strength, but when I try to do anything (i.e. go to google.com), I get a message saying "cannot connect".

UPDATE:

I didn't think it was a problem with my router or network, because my two computers work just fine on it, and the phone was connected to the network before I did the reset. However, I decided to turn the router off and on yet again a few more times, and finally, that seems to have fixed the problem.

HOW STRANGE! and how fortunate..