Yes, both AVG and avast have uninstall tool, they can help in case you get problem during uninstall. AVG: http://www.omidfarhang.com/computer/how-to/uninstall/security/avg avast: http://www.omidfarhang.com/computer/how-to/uninstall/security/avast even more: http://www.omidfarhang.com/computer/how-to/uninstall/security
If you need any more help I will be glad to help so.