Creating a reboot task with option to defer

Greeting all;

I'm having trouble finding what I thought was an easy task.  Essentially I need to reboot user's PC's occasionally in my troubleshooting efforts to hunt down machines that seem to have stalled with patching.  Additionally, I need to be curteous to the users and give them the option to defer the reboot with some sort of warning message similar to the one given with the completion of a patch cycle.  Simply scheduling reboots in the middle of the night won't fit the need.

How can I create a task to reboot a PC with a warning and option to defer?

Any advice is appreciated.  Thanks in advance for your time...

- Michael