Win 7/10 Dual Boot program/app/registry questions

[Fangoroth]

I apologize if the format of these questions is terrible, I'm better at putting parts together than I am fiddling with software.

I currently run Win7-64 off of a 60gb SSD (which is almost full) and have been considering doing a fresh install. If I were to bother, I would have to burn a win7 ISO to a flash drive and boot from that as I cannot find my CD ( I did manage to use something from another forum to find my key however so I can still legally activate the new install). I figured that, since my current SSD is a few years old and has 0 extra space on average anyway, I may just buy a 500Gb or even a 1Tb drive since they're currently on sale at my local Microcenter. I also figure this would be a good time to try upgrading to Win10, but I want the option of switching between 7 and 10 to try and smooth out the adjustment.

The plan was to partition the SSD into 3 sections;
Win7 partition
Win10 partition
Program/game install partition

I would like to use as little space as possible for each version of windows, and had hoped to install ONLY windows/drivers in their respective partitions.

To this end, I had hoped to install programs (Steam, winrar, firefox, etc) to the program partition. I currently have MOST programs installed on a separate drive, and have found that when I have had to reinstall win7 to the SSD in the past the system does not automatically recognize or find programs installed on a separate drive. For the sake of convenience, I would like to be able to simply search seldom-used programs, or games, in the search bar (which in the past it would not do after a fresh install when trying to find programs on my current install drive).

Is there a way to have win7/10 recognize installations not done under that specific OS? Would I have to install duplicates of each program to each OS separately? Is there a way I can have the registry auto-recognize programs on the install drive? will I just need to run the installer on each OS and point them to the install drive and do a repair-install so that both recognize the location? Is there another option I have yet to consider?


And as a followup question, should I decide to eventually forgo Win7 and stick with 10, can I create a backup of my Win10 files, format the drives so that Win10 can use Win7's space, and then reapply Win10 to the new space? Can I just wipe the 7 drive and extend the 10?

Again I apologize, I'm not much good with software and really am better at just building rigs.

 

[Fangoroth]

Well, hopefully someone will notice this before the sale ends so I can pick up a cheaper SSD. May just experiment with this and hope for the best, but it'd be really nice to have some tips.

 

[alphanumeric]

The two OS can not share the same system/program files folder etc. If that's what your intent is? Also, when you install a program it makes many entries in the registry etc. Just preserving the folder they are installed too isn't enough. Without the registry entries the program will not run. You have to reinstall them for them to be fully functional.

 

[Andyrids]

For small important and useful programs I look for portable versions and always use that if it is available as they just reside in the folder they were extracted to and create their own .ini files for the configuration that way you can share it between a duel boot system without worrying about registry entries as there is none...

Some of the portable programs will create temporary files and entries but the program will remove them once it is closed Thunderbird portable for example does this as for as I recall...

PortableApps.com - Portable software for USB, portable, and cloud drives there is lots there you don't have to install them to a flash drive just point the .paf.exe to the folder / drive you wish to install / extract to.