This stalls because of the hand coding you did in the Insert server behavior code.
It is trying to get the data from the insert to populate the Server Behaviors panel and runs into problems when it gets to your hand code.
The best solution when hand coding is to make sure you break the inspection early in the code. So for instance add a comment after line 10 like:
// hand coded insert
Adding that line would prevent Dreamweaver from trying to interpret the server behavior and prevent the crash.
(You can probably open the page with notepad to add the line at this point)