Got it! With a whole half of a day off left to play it ... once I finish the bit of writing I was working on, and if I drop the book I was going to read.

Installed Heroes 3 Complete, checked the readme and found that it does include both add-ons, which it installs as part of the default. It seems like this is a reissue of the old bundle edition. Loaded it up, and I can't find a version number. Am I likely to need any patches? Also, is there any way to change the resolution? The default is pretty unkind to my eyes on my LCD monitor.

Installed Heroes 4 next. It also has both add-ons. Again, no idea of version number or where I stand on patching. Help? My guess is that if there were patches after the second add-on (whichever that was ...) I might need them.

I had to laugh at the system check messages put out by HOMM3 and 4.
Setup has detected that you have 2GB of memory available on your system. The game requires 32 (or 128 for HOMM4) MB to run. The game may run sluggishly, become unstable, or fail to run at all. DO you wish to continue?"
Oh noes!!!1!1! Sorry, am in a silly mood

Now to install HOMM5.