readersinc wrote:
Should I forget about speeding up this Mac and consider purchasing a new computer?
It really depends on if you like throwing money at problems or if you want to try to improve what you already own. A newer Mac is normally faster, but you may not need it.
2GB of RAM is a the bare minimum for 10.11 as Apple state in the requirements…
Upgrade to OS X El Capitan - Apple Support
Any computer running on the bare minimum will have issues doing multiple things - you should just quit all the apps running in the Dock.
Activity Monitor is not intended to be used like you describe - if you force quit the wrong process or app the computer may crash, become unstable or lose your data. Please stop looking at that in an attempt to kill processes, it is meant to allow you to diagnose the current state, force quit isn't designed for this.
You can purchase more RAM for your Mac, that will allow it to do more tasks, otherwise you have to accept that it is best to do one or two tasks & quit other open applications.
An Apple store may help you if you need advice on fitting RAM, I think that model may support up to 32GB (Apple state 16GB, but newer RAM modules are larger & seem to work) but you should check the model identifier in System Information. That appears under the Apple menu, hold the option key & open the Apple menu (a.k.a alt key).
RAM is normally easy to fit, but you may want to get someone technical to do it for you. There are user guides made by Apple for fitting RAM in each model.
Slowness may also be caused by other software or slow hard disks. Do you want to create a report to show what is installed? Etrecheck is designed to do that…
http://etrecheck.com/
P.S. Apps like Clean My Mac & Mac Keeper will use more RAM, so they really won't help your predicament. Most of their tasks seem pointless to me.