Are you looking at the Adobe document on System Requirements for Premiere Elements Windows and Mac
The information that you give for your Premiere Elements 11 Mac looks like it came from there.
I am strictly an Elements Windows user, and I know that the document is not up to date. I can get even Premiere Elements 2.0 to work well on Windows 10 64 bit.
Suggestion: why don't you download and install the tryout of the current version of Premiere Elements Mac (version 13) and determine if its performance it better than what you are getting with Premiere Elements 11 Mac. That might help in the decision making about computer operating system and factors related to 11 performance.
Also, be aware that Adobe is expected to release a new version of Premiere Elements (presumed named Premiere Elements 14) September October 2015. Version 13 will be the tryout until 14 is released. Then 14 will be the tryout. The tryouts have all the features.
Yes I ready the system requirements online and then on the box before I bought the install cd. I don't want to have to buy new video editing software if I don't have to but it has so much lag now its hard to get much done!
Thanks for the reply.
I was not suggesting that you buy Premiere Elements 13 Mac, but rather use it as a troubleshooting tool to try and sort of the factors related to the lag in your present Premiere Elements 11 Mac on 10.8.
Have you gone through the usual drills on increasing Premiere Elements performance...
a. identifying factors that make thing better or worst related to properties of your source files, project presets,
b. effects applied, rendering times
c. where the Scratch Disks are pointed and how much free space is at those locations
d. need for Mac cleanup and optimization...
e. video card/graphics card updates
f. any antivirus or firewall factors
g. drives with low data transfer rates and storage location of project's source files
We will be watching for your progress as your schedule permits.