edit:
Thanks for the reply, unfortunately this has not solved the issue I am having. At first it was slightly working better and wasn't lagging as much but now its just as laggy as before, and it is still freezing my computer to the point where I have to smother the power button till it shuts down. Now I know it is Parallels that's causing this issue because before I updated to Parallels 9 I was on the previous version on a iMac with lower specs and there was no issue. Now I have tried to see if it was an issue with my mac mini causing the issue by trying it out on my iMac and I am able to replicate the issue on both computers with the latest version of parallels install (Parallels 9).
Computer specs:
Computer: Mac Mini Server Late 2012
Processor: 2.3 GHz Intel Core i7
Memory: 8GB 1600 MHz DDR3
Graphics: Intel HD Graphics 4000 1024 MB
Software: OS X 10.9.2
Last edited: May 16, 2014