Colin, I have not had to use a Win 10 PC as of yet. I won't use it due to multiple issues with privacy. Wipe and install Linux is what I usually do.
To continue to inquire, a couple questions,
1) Is 32Gb the only storage you have as a HDD ? If so Windoze will most likely need all that space since it has a different and messy filesystem type(ntfs). I used up a 60GB very quickly.
2) Are you able to upgrade the HDD to a larger disk ? If so there is a way to bit by bit copy the old HDD so you retain Windoze on a partition on a new HDD.
As far as Virtualbox and Windowz, I run Win7, and OSX at the same time on LinuxLite as the host OS. No issues at all, but I have a powerful laptop with i7,16gb ram, 2 1TB hybrid HDD's, and Nvidia graphics.
I gave up on the small netbooks due to speed and lack of versatility issues. Portability is great for 1 OS on them, but you sacrifice power.
Retaining Win10 and Dual booting Linux I recommend upgrading the HDD size, whatever type it be.
OR you could Use Unetbootin and a micro USB drive, Install LinuxLite with persistance on the USB and then avoid the above suggestions. That way you could have the best of both worlds, but UEFI may present an issue with booting. Not sure if you can boot Win10 after turning it off like you can in Win7.
Maybe try and use a USB drive and install Linux to that, boot loader as well on the USB drive. Then you would have to enter boot menu of BIOS to choose what OS you want to boot every time.