New installation of Sparky 7 Mate..now freezing

[thomastt371]

I have been using sparky 6.3 without any problems.I decided to completely remove version 6.3 kde and install sparky 7 with mate desktop.When i burnt the image to a Disk,there was a problem writing the image Checksome and it would not start?I decided  to carry on and the image installed successfully though it was very slow to install.On running the Operating system i have had several instances of the system completly freezing which has ended in the system needing rebooting.Has anyone else had this problem and is there a fix for it?  Michael Hirons