Dumb installation question

So I’ve downloaded 2.48. When in install it, will it overwrite the previous version of Blender, or will it create a folder for the new version of Blender?

Create a backup of your Blender directory just in case.
Whenever I install Blender on Windows, it overwrites the .EXEs and some text files, I believe it adds scripts and the like, and leaves the rest of the directory alone. You should be fine to upgrade using the installer.

If not, you can always restore your backup, then download the .zip and move files manually.
And that’s not a dumb question.

Thanks, I use an external hard drive to back up stuff, so it shouldn’t be a problem.