I would doubt if this is to do with upgrade but you may never know.
There is never SP07 for any version so probably SP05.
Run system diagnostic on those machine to make sure every thing is set up correctly. If you still see issues then report to your VAR.
Also this could be a helpful post in setting up the codes to close and open SOLIDWORKS after a limited number of files. macro works great 500 times, then crashes
Thanks for the reply Deepak.
After continued evaluation I see now that it is actually the Solidworks Resource Monitor that is crashing and causing the lockups.
I found this website and will be looking to kill the resource monitor as well: