Internet connection services not running Windows 7 Home Premium x64

I've had a cascading series of problems since mid-December 2011 with my Gateway PC running Windows 7 Home Premium 7 x64. I was finally able to fix my Error 1402 issue that had been plaguing me. Unfortunately, I've now somehow completely disabled my Internet connection. 

I did try to follow some instructions I found around the basic error mesage when I open the Network and Sharing Center, which has a red X over a wireless signal bar. The error message in the Network and Sharing Center window is "The dependency service or group failed to start." I did not document the changes I made to some of the Services, though I don't think that matters so much once you get to my question. The two Services I had tried to change were the Security Center and the Windows Management Instrumentation.

I'm pretty sure this happened due to some changes I made to the registry relating to the Error 1402 issue I previously had which was affecting my ability to update some of my software.

I can view and access part of my home network, basically other PCs when they're turned on. I can not, however, view or access my router.

Here are my questions and I've tried to find the answer on various Microsoft sites, including TechNet:

1. What Services in the Services (Local) are required at a minimum for Internet connectivity to function?
2. What are the specific settings for these Internet connectivity Services, especially their Startup Type and Log On As?
3. Are there any other services or processes that I can change or use an automated tool such as Mr FixIt to address this issue?
4. Is there a method or tool for restoring the default Internet connectivity without resorting to resintalling Windows?

Some of the things I've tried including Safe Mode with Networking -- does not give me Internet connectivity; Last Known Working Configuration -- does not give me Internet connectivity. I've run my system repair disc but there do not seem to be any options that will help other than reinstalling Windows. System Restore does not address this issue.

Thank you for your time and help.