Acronis is the bomb when it comes to puting OS's where you want - the order doesn't matter.
I have installed on Laptop with Win95, Win95OSR2, Win98, Win2k and also Dos 6.22 (all because dongles don't work too well in Windoze........sometimes)
However, for your support of multiple pgms and os's, have you considered using VMWare?
I'm in a similar position to you, and got sick of swaping disks in and out of my machine - not to mention any hardware detection issues etc..... started using VMWare and most of my concerns have gone away.
I've also kept an IDE port spare with a really long IDE cable on it for those times when I need to 'rescue' a customer's disk.