What's the difference between Safe Mode and Selective Startup

I have got a software that has stopped working. But it will work when I boot my computer in safe mode? It will however wont work if I do msconfig to get the system configuration utility, and then select "Selective Startup" and uncheck all the boxes and restart. So can anyone tell me what does this minimal boot do that safe mode doesnt do? Thanks

It will actually load all the drivers that safe mode doesnt do. It will load in your selected screen resolution instead of the minimum one. There are likely other things but those are the main ones that I can actually remember at this time now.

Have you checked to make sure whether the software is compatible with your system?