100% cpu usage with windows explorer and internet explorer

I have been unable to use windows explorer and internet explorer for the past week. Every time I try to start one of these (eg, my computer, network connections, internet explorer), the task manager tells me the application is using 100% of CPU and the application will not open. I can use task manager to shut down the process for either of these, and then I can start explorer.exe to get my task bar and desktop back, but I cannot open an explorer windows.

Can anyone suggest any things I should check for, or some way of "resetting" these applications? It is becoming very frustrating to try to resolve this problem since I am in
Europe now and without being able to even open network connections, I can't even connect my laptop to a wireless or ethernet network, or to a dialup ISP. I can call the Dell 1-800#, but I have to pay to make the from here. It's not practical when I have to wait 15 minutes in the queue before I can even talk to someone.

Alternatively, in a pinch, is there anyway to enable a network connection
without going through windows explorer?

Thanks.