1. Ranking a video in YT is simple as soon as you stay away from heavy niches like "weight loss". Most important factors which Youtube counts are obviously the title, description and tags. Try to make these keyword optimized and eye-catching.
Titles should be under 60 characters and try to include the keyword to appear first. Description should be keyword optimized, contextual and with keyword stuffing avoided. Tags try to keep under 3 in this way you will have high density so Youtube will think that the video is targeted only to those few niches.
In some niches the vital factor is backlinks. Backlinks matters a lot, contextual articles with keyword anchor linking direct to YT video helps but the same is with social bookmarking or any other link. Also embeded videos gives viral effect so this helps a lot, you can do that by submiting the video through video aggregators (clipshare) . Adding a few natural comments, likes/dislikes and views will make it. These are the most important factors which will help you to rank in YT search index.
2. I don't know any tool which can do that but in my opinion there is no point to spend time on finding video backlinks. In niches where competition is high is nothing more about the quantity. Add more backlinks, add more views, likes and comments. Don't stop till you get 1#, then the traffic will do everything for you.
3.4.
I'm not familiar with Google tools since I don't use them. I don't like to put everything on table about my website, making more easy the job for Google. I'm afraid I can't help you with this.
5. I remember I read somewhere that Google Webmaster tools offers you the chance to target desired country by simply selecting from the dashboard. Hosting your website on servers in the same country will help to show Google what country you want to target.
