MAC OS - do I need an upgrade? Is my MAC eligible

I have a MAC with the following:
iMac early 2009
Processor 2.66 GHz Intel Core 2 Duo
Memory 4 GB 1067 MHz DDR3
Graphics NVIDIA GeForce 9400 256 MB
Software Mac OS X Lion 10.7.5 (11G63)
When I run software update Apple says no upgrade needed, however, many of my applications are now telling me they no longer support my current OS.
Is there an upgrade available for my MAC or is it just too old?

Welcome to the Mac Forums.

The reason Apple is telling you that no upgrade is available is because you have the latest update to Lion (OS X 10.7.5). However, your machine can run the latest version of OS X El Capitan (10.11.3) and you can add more memory. (recommended) Your iMac can take up to 8 GB of memory.

You should be aware Apple has ceased all updates, and security updtes, for Lion OS X.7. As chscag suggests, go to Crucial or OWC, increase the memory to 8GB and download and install OS X.11 El Capitan. Your iMac has two memory slots so you would be looking at 2 x 4GB modules.

I'm running El Capitan on a 2008 Macbook. Your 2009 iMac will handle it no questions asked, and the OS upgrade is free through the app store.

Although you can upgrade to El Capitan and run your computer with 4 GB of RAM, I agree with others that you should upgrade to 8 GB.

How difficult is it to add the additional memory? A do it yourself task or take it to. A repair shop? Where would you buy the proper memory?

No it is quite easy. Go to the OWC link and they have vieos on the page. The 2x4GB modules cost a total of $58.00 (on special) and if you go to your model and click on the 'Install Video' in blue, you will see how to do it on the next page, top item is memory and install applies to 2007- early 2009. Simply remove one screw, and off you go:-


http://eshop.macsales.com/item/Other World Computing/8566DDR3S8GP/