BleepingComputer.com: Nonresponsive windows

Recently I bought an external hard drive to backup the data on my laptop. I don't know if it has anything to do with the issue I'm having or just a coincidence.

After installing the HDD, Vista started running really slow. Now it's gotten to the point where after opening any type of window, to included web browser or document file, the window will become completely unresponsive and I have to wait up to 10 mins. to restart. While I am posting this I just received a message that "Host Processes for Windows has stopped working and has shut down". I don't know what that means. Is this something serious or an easy fix? I will run a disk check and post the results. But any help will be greatly appreciated.

External HDD is a WD My Passport. Laptop is a Toshiba Satallite running Windows Vista.

This post has been edited by spdfrk78: 04 August 2009 - 12:49 AM