Get Default Browser - Process Monitor ?

Firstly im aware that the code below will auto run the default browser.

Code:

But i need to find a way of finding out what the default browser is. Is there a registry setting that displays this? also whats the best way to monitor for a process start or exit?

I was thinking about making a listview that updates every second checking for new entrys or entrys that have gone. But is this the best way if i only need to monitor 1 or 2 proceses?

I did write(and worked before)

Code:

But thats not working now.