I had the same problem with my mac. After going through this forum i was able to fix the issue.
A few days ago my outlook had stopped working (it wouldn't load). To fix that, I created a new outlook identify (i.e. and created all outlook accounts from scratch). Within 1-2 days of that I had started trouble with my mouse and keyboard freezing. It was never a hardware issue.
I wiped out my office installation and did a complete new install. I haven't had the keyboard and mouse issue since than.