1. You can edit the video with any mainstream video editing software. If you have windows, you can start with using Windows Movie Maker... it's free, so why not!
2. If you want a popular high-end video editor, I would suggest Adobe Premiere CS3. I use this all the time on my YouTube videos and it's comparable to Apple's Final Cut Pro (which is the best you can get.... if you have a MAC)
3. YouTube videos are automagically appear in Google. Now, if you want to appear at the top of search results for a given keyword... make sure you put in your keyword or keyword phrase at least once in the video title, twice in the video description, and name your actual video file what your primary keyword or keyword phrase is.
As an example... if your keyword phrase is "Beyonce Ringtone" then here is what you want to do:
Video Filename that you upload : beyonce-ringtone.avi
Video Title : Rare Beyonce Ringtone Video!
Video Description : Check out this rare beyonce ringtone video! If you want a beyonce ringtone, then this video is for you!
You will also want to make sure your ad copy is compelling enough to entice someone to click... because your ad copy will be showing up on google as well as youtube.
If your video is a hit, then you will have hundreds of video scraping sites index your video also!
Want a real world example?
Last Halloween Season I made a goal to create a viral video that showed off funny halloween costumes.... and I wanted to watermark the video with a link to a domain I own that was a redirect to a costume outlet via: my affiliate link.
To say the least.... the video was a massive success.
Go to google and type in "Costume Tribute" and you'll see it in the #1 spot
Here is the direct link : http://www.youtube.com/watch?v=l6PurBtZTz4
Good luck!