A:AnswerIf you purchase Office yes you can stop renewing 365 for a handful of years. That time frame is up to Microsoft. No it doesn't effect your documents except now you'll have the option to take them off the cloud & actually keep your own files, at least for Word,Excel & PowerPoint. The other apps you'll have to use the free online version for like Outlook. As far as uninstalling & reinstalling that's a yes.
A:AnswerI do not have a good answer as i was going to do that same thing for my older computer but found a really good price & bit the pencil & bought a new computer instead.