Daydreams, please clarify why you need to remove the whole software and make a completely new installation.
The answer will depend on what you want to achieve in the end.
If you need to move your site from one hosting to another, this will be one solution.
If you need to update your software, this will be other solution.
If you have an errors on your site, then you need to enable DEBUG_MODE and fix them.
If you mean transfer user data from Oxwall to Oxwal site and both sites have the same software versions, you just need to do mySQL transfer and copy row userfiles folder. If not, please point out versions because transfer conditions depends on them.