Most of the time I find crashes like that in PHP due to version mismatches between IIS and PHP, or the same with extensions.
Ensure that the whole stack uses the correct version, architecture (32-bit vs. 64-bit), etc. and that they all match and are suggested to be used with one another. If using FastCGI, make sure it is patched and using the latest version. (That link is for IIS 7. Is there a reason you're using such an old version of IIS that you can't move to something not 10 years old? You're going to be plagued by problems if you don't upgrade that.)
If you're having startup problems or only problems when certain extensions are used, try disabling extensions to see if you can get it to launch without them to track down if one is causing a problem.
Try increase the logging levels by setting them lower, like to the Debug level perhaps.
If none of that works, you could try running Apache on Windows to see if that helps. Or just php.exe standalong to check if it is PHP-only vs. PHP + IIS problem.