Don't panic about the firewall/connection thing until later
At least your LW opens now.
Did the Java update fix your lag issues?
You don't have to turn your firewall off. Just make sure that you're only using 1 (remember XP has it's own) & that it's configured properly. Check out the sticky below...it has heaps of info & fixes for connection/firewall problems.
Connection problems? Check here first!
If you're still stuck, tell us your details
System details - help us to help you