I've done an upgrade to win 10 a couple of times and everything was left in the same place and all progs worked fine, I'd back up any docs just in case though.
If you don't have the product key it's best to upgrade first which will give you a digital licence for win 10 automatically taken from your previous OS then do a fresh install to get everything nice and clean, worth investing in an SSD and doing the fresh install to that as it will speed up your machine no end and you can still run from the old one if you run into trouble.
The free upgrade officially ended ages ago but still works fine, download the win 10 iso from microsoft and use their tool to create a bootable usb stick.
If you use firefox for internet and thunderbird for email they are easy to copy your profile folders over and everything is as it was, even stored passwords.
Many Thanks
I think I have a Win 10 DVD ready to go. I'll fire up the NAS and do some backing up
