It's been a while since I upgraded, but I believe if you have the current version still installed when you install the new one your settings will be saved. Just to be sure, you can save your settings with the Copy Settings Wizard before downloading the new version. See Can I save my SolidWorks settings for when I upgrade, or to share with another user? if you aren't familiar with it.
It's pretty much the same since most of them are saved in registry unless there are some changes in the new release
The other way is you can save settings before upgrading so you can run the settings just in case some missings