I'm thinking of building a new computer.  I am considering making it a dual boot with Windows 10 on both partitions or maybe 2 drives, one a HHD and one an SSD.  On the HHD I'd run Windows 10 32 bit and Windows 10 64 bit on the SSD.

I am of the belief that I could run 16 bit programs on the 32 bit version of Windows 10 and I have several I don't want to lose.  That is the reason for the Windows 10 32 bit version.

What I'm curious about is if the system has 16GB of memory will I be able to run the 32 bit version knowing full well that any 32 bit version will only be able to access 4 GB of memory.  Will it still run and just ignore the remaining 12GB?