I have a Dell laptop that was going through rough times with trojans and such. I paid for and downloaded some AVG software that cleaned up some of the problems but some still remained. The last issue I was able to see happen were reports of "critical errors" and virus infections and such with extremely limited use of the computer to fix them. Now, the computer will not start in normal mode and when I try to start it in safe mode (using any of the options), it locks up and nothing happens. What are my options? Thank you!!!!