Question : Vista laptop won't connect to Internet, but XP will, via same network. What settings / troubleshooting can I do to resolve issues?

I'm logged in as Admin, have comcast modem, and currently the Network and Sharing Center reports:
PC Name  --Greenline--Unidentified Network--Line_with_Red_X--Internet as the map of the network.

Access is listed as "Local Only". Signal Strength is good.

IPConfig/ release /renew is not working.

Ideas?

Answer : Vista laptop won't connect to Internet, but XP will, via same network. What settings / troubleshooting can I do to resolve issues?

What really works for me and I do it with every Vista computer I get in my hands, is to disable the IPv6 protocol.

Here's how to:

Start menu -> Right click -> Properties on the Network icon. In the left column, click on manage network connections.
Right click -> Properties on your wireless connection, uncheck the IPv6 protocol.

I recommend you do the same for the wired network. Hope this helps.