Please OOT help me with my computer problems

[Paluka]

My desktop no longer recognizes IP addresses. I have "limited or no connectity".
All my other laptops, Tivos etc work fine.
I've tried more than one network adapter.
I have no "Security Center" in my windows services. It is not running, and doesn't show up when i run services.msc. I cannot change my windows firewall settings. Is this the problem? How did this happen?
I'll gladly repay any help with poker help. I'll go over hand histories or whatever. I'm better at poker than I am at fixing my computer.