uninstall any useless software on your PC.
if Firewall/Anti-Virus isn't the cause and you tried System Restore then last thing is reformatting your PC (re-install Windows).
First I would like to say that I really like your wallpaper.
Now on the topic, try disabling all the services that boot from msconfig and than restart and try connecting...
If you want I could try and solve your problem by assisting you remotely via TeamViewer http://www.teamviewer.com/en/index.aspx?cdsplit=C .(Send me PM with password and ID if you want me to help you in "person")