The only reason your machine wouldn't run Windows 10 is if there's something 'odd' about the BIOS or some off-the-wall hardware component for which there is not yet a Win10 driver. Here's one article on how to check compatibility:

http://www.groovypost.com/howto/chec...ns-windows-10/

You're wise to have separate partitions for O.S./apps and data. You can also download a Windows 10 DVD and install from scratch if you want. If you have the 25 digit Windows 8 key - and you can retrieve it if you don't - that should activate a clean install of Windows 10. You do need to do this by the end of July. Once a Windows 10 install is activated, Microsoft's activation servers remember the 'digital signature' of your machine. If you have to re-install Windows 10 it should automatically activate.