No Internet Connection after I had one

After doing a fresh install of Vista Ultimate addition I automatically have a
working connection to my wireless router. After installing a few programs
and restarting I still have a connection, but then after a restart when the
system comes back up, no connection. The only thing I messed with that I can
think of was adding a shared folder. And now it's greyed out so I can't turn
it off. I tried multiple adapters and multiple access points and every time
it sees the network, but can't get an IP address and it can't connect to the
Internet. If I put a manual IP address in I can see other computers but not
the admin page of my router and because of which I belieeve is also
preventing me from seeing the internet.