You can debug .mdmp (minidump) files with WinDbg
or Visual Studio.NET.
In WinDbg documentation, look at "Crash Dump Files" topic.
For Visual Studio.NET information, look here:
http://www.codeproject.com/debug/postmortemdebug_standalone1.asp
http://msdn.microsoft.com/library/en-us/vsdebug/html/vxtskCrashDumps.asp?fra
me=true
I don't know how to debug .hdmp files - I never tried.
Regards,
Oleg