Can not uninstall McAfee, access denied and I no longer use it.

I did not like McAfee which I got with my Dell a year ago. I uninstalled mcafee and installed Norton.

Even though mcafee appears as uninstalled on my program list, many components remain on my hard drive under program files. I can not remove them. File called personal firewall is still there and if I try to delete it, I get: "Cannot delete localized Dll: access denied, make sure disc is not full or write protected and that the file is not currently in use." For the Agent file that is still there  I get: the same message, except it says can not delete: mctskshd.exe

 

It wound not bother me to have these files there, however what is bugging me is that I get a pop-up that comes up twice each and every time I open up that says, I need Mcafee and says that I need to reinstall it!!!! I had the disc for mcafee so I uninstalled Norton, reinstalled mcafee and then uninstalled it again, and got no where. Nothing I have tryed will get rid of this pop-up and I am ready to scream!!!!!!! Dell and Mcafee have given me zero help with this. Mcafee does not want me to forget them and believe me after this I will not.  I will avoid them like the plague and tell others to also. Any help you computer experts can give me would be so appreciated  Thanks, Julie