1. centaur78 is right. You are starving from lack of RAM - just get more RAM, as much as your mobo can stand. Check with the system scanner in this link what is possible and how much it costs: RAM Memory Upgrade: Dell, Mac, Apple, HP, Compaq. USB drives, SSD at Crucial.com
2. Your task manager snip is pretty useless because a) you did not 'Show processes from all users' and b) you did not prioritize the picture by CPU time so that the high usage processes show on top.
3. And yes - you have too many processes. Disable all startup programs - except the McAfee protection modules
4. Mid term you may want to get rid of McAfee and use MSE instead. But make sure you uninstall McAfee with the MPCR.exe - else you'll get a problem.
5. At this moment I think you are dying from page thrashing (because of the lack of RAM). Check that in Resource Monitor > Memory tab > the graph on the bottom right.