Q: my apple is running slowly

Completely uninstall Mackeeper!!!!

It is complete "crapware" and should be avoided at all costs!

This is what is slowing your iMac.

http://www.macexpertguide.com/2012/11/16/uninstall-mackeeper-2012-2011-mac/

Also, if you like, your model iMac can take a total of 6 GBs of RAM max.

You can replace one of your 2 Gb RAM modules with a 4 GBs RAM module.

Correct and reliable Mac RAM can be purchased from online Mac RAM sources Crucial memory or OWC (macsales.com).

Here's the link for the 4 GB RAM modules from OWC.

http://eshop.macsales.com/item/Other%20World%20Computing/6400DDR2S4GB/

Good Luck!

See:

Mac Maintenance Quick Assist,
Mac OS X speed FAQ,
Speeding up Macs,
How to Speed up Macs,
Macintosh OS X Routine Maintenance,
Mac troubleshooting: What to do when your computer is too slow,
Essential Mac Maintenance: Get set up,
Essential Mac Maintenance: Rev up your routines,
Maintaining OS X, 
Five Mac maintenance myths and
Myths of required versus not required maintenance for Mac OS X for information.