Hey Zeno,
This is actually quite easy.
While in the playback window of the YouTube video you wish to Embed...
1. Copy (to your clipboard) the contents of the Embed box located to the right of the video.
2. Go back to Dreamweaver and paste the contents of your clipboard into the code window anywhere in between &
3. Repeat steps 1 & 2 for each video you would like to Embed.
I hope this answers your question.
Joe Truesdell
Technical Director
http://www.globalmechanic.com