Try this as a first shot.
It looks like most of the crashers vanish or get minimised for some of us when the GPU Playback is disabled.
This setting can be found in the "Edit>Preferences>General"
As EditMachine suggested, disabling that checkbox could help.
In addition, you could try un-docking the monitor window. To do this, click on Window menu->Show docking headers. Then drag the pane that says "Monitor". See the display in this one by pressing Play or the space bar. And then you could restore it into the workspace. (If that's the way you like it..)
Holly, the file format utilized by a Flip camera is not in an editable format that will work easily with PE.
The fact that you were able to edit a video once, will only give you a false sense of security, leading to eventual heartache.
REVIEW this thread from the FAQ's on Flip cameras, and convert your files as recommended for use within PE:
If you convert successfully, your level of frustration will decrease dramatically...