It depends. Obviously, you'll want to put your HTML files in the public_html folder. The other folders though (the ones in public_html starting with underscores) are, I believe, for Frontpage. If you don't plan on using Frontpage then I suppose you can get rid of them. I think you can also get rid of the .htaccess file in public_html if you don't plan on using Frontpage.
My public_html folder could be absolutely empty except for an index.html file and your web page will still display fine.
(Remember not to erase random folders that are NOT in public_html!)