Shear coincidence I purposely upgraded my sisters Win7 laptop to the latest Win10. I was surprised that my USB 3 docking station works with her laptop with full support even though she only has USB 2. Only my mouse was working with the docking station with Win7. Now two external monitors and Ethernet also works with the upgrade.
Her office 2000 also still works after the upgrade. Note she has a office 365 subscription as well. She hasn't been using this laptop for several months because it has issues. Track pad is broken. She replaced the keyboard a few years ago due to kids spilling pop. Her two kids have a Surface each now (got 18 months ago). I just have to rewire and solder her power brick cord and she can ditch the APC Universal Notebook Battery system I gave her to supply power. I don't think it supplies enough power to charge the laptop battery when being used, which is probably one reason for "issues".
Anyways, Win10 looks good.