I am a newbie to videophotography ...

I have a Canon HG10 and Vegas 8 trial version.

What is the best format to Render the best quality for viewing?

I would like to share on DVD and also by uploading to Acid planet or YouTube.

Thank you in advance.

DVD: MPEG2 for video and AC3 for audio.

YouTube has a help page that gives you the recommended file types and other settings for export.