You can do these two checks very quickly and also answer the questions when you reply.
1. Load CCleaner and turn off the option at Options > Settings > Automatically check for updates to CCleaner .
Exit CCleaner and try loading again.
2. Use this small and fast scanner for malware.
The program is free. Get the free version for now.
Just press download and ignore everything but selecting the MBAM download site. Don't mess with any free scans or such offered at the download sites if any. I personally used the Download.com site. http://www.malwarebytes.org/mbam.php
Once installed select Update tab and update the program.
Then select the Scan tab and do a quick scan. It only takes 5-10 mins to do a quick scan.
What anti-virus programs do you have running on your PC ?
When was the last time that you "defragmented" your hard drive ?
Do you always leave the options on to clean the Internet Explorer areas also ?
Do you have the Firefox options set on the Applications tab ?