There could be a number of reasons for the intermittent problems, so I would suggest due to the newness of the computer that you contact the retailer for advice.
Just a few questions in the meantime:
Is the mouse new, wireless, wired, and was this supplied with the computer?.
Have you installed 'extra' software, that might not be compatible?.
Loose components, moved during transit?.
What happens when you do a reboot. Is the computer stable then freezes later?.