Emails are not enabled on this instance so PeerTube won't be able to send an email to <x id="START_EMPHASISED_TEXT" ctype="x-em" equiv-text="<em>"/><x id="INTERPOLATION" equiv-text="{{ registration.email }}"/><x id="CLOSE_EMPHASISED_TEXT" ctype="x-em" equiv-text="</em>"/> explaining its account has been created.
You can import any torrent file that points to a media file. You should make sure you have diffusion rights over the content it points to, otherwise it could cause legal trouble to yourself and your instance.
The main threat to your privacy induced by BitTorrent lies in your IP address being stored in the instance's BitTorrent tracker as long as you download or watch the video.