Mocha AE Crashes When Tracking

Your Intel Graphics card is probably the source of the crash. You could also be running out of system resources. There is a fix for the graphics card in the Mocha AE preferences. Try turning off display acceleration.

This is how I would approach the project: Split the footage layer on the frame where the monitor goes out of frame because there is no reason to work on frames that don't need work. Apply Mocha AE to the first part of the shot. To minimize the system drain use 4 splines on the same layer (use the Plus tool) to identify the corners of the monitor and a point on the wall that will not go out of frame. Make sure Perspective is turned on in the tracking options. Turn on Surface and add a grid so you can precisely line up the corners of the track to the monitor screen, then track, save and return to AE. Here are some screenshots. First Set preferences:

Set up the splines tracking options:

Switch to Layer Properties and add a grid and turn on the surface:

Run the track. The grid on the surface makes it very easy to see if the track is successful and it does not slow anything down.

This is the final composite. I just used a copy of the footage and added a few effects and used a blend mode to improve the composite. 

Maybe your computer doesn't have much RAM, or GPU acceleration, or processor clock speed so when you start tracking it crashes. Give us a little more detail about tech specs of your system and the clip you want to track.