[I would love to upload some videos in YOUTUBE. My question is simple. How can I take that videos into the first page.]
The same SEO principles apply to youtube video pages like any other page. You optimize keywords in video titles and descriptions, make sure that the content is useful and link-worthy, and promote the heck out of it just as you would with any other page.
There are some promotional methods that are somewhat unique to videos, like embedding opportunities at social networking sites (like youtube). It’s the same principle behind syndicating articles, press releases and RRS feeds. As always, content is king, so make your video content link-worthy to get the most out of your promotional efforts.
SEO efforts are, to a certain extent, wasted when applied to poorly crafted content.
SEO is a process that works best when combined with useful content and a solid promotional effort. While there is no direct influence from the video content, there certainly is a very influential impact from a video that goes viral due to the value of the content. The natural backlinks you receive from useful and/or entertaining content are among the most powerful influences available for your SEO.