Can you login to all the accounts now? Was the 0xC0000022 error message displayed in blue full screen? (Matty: sorry, I thought it was just the app crashing, not a BSOD).
About the icons, try rebuilding the icon cache. Download and install
Microsoft's Powertoys for Windows XP, run TweakUI, go to Repair, make sure "Rebuild icons" is selected and click Repair now.
About the internet, how are you trying to connect? What's the problem? Any error messages?