Thanks for your post. I would divide this issue into 3 separate problems.
1.) Unresponsiveness report. This could be caused by something which is project-specific. May I ask you about the project you are developing? Would you be willing to give us access or if not provide information about it, e.g. composer.json?
2.) HTTP 500 - there was some unhandled exception which caused IIS to terminate the request. When you are debugging you should be able to break on unhandled exceptions
https://docs.devsense.com/en/vs/debugging/exceptions . If you are not debugging you should be able to see the issue in php error log.
3.) Crash during debugging - what kind of crash do you mean? Crash of php project (The HTTP 500 you are mentioning) or VS ?