Youtube video start point.

I would like to know if there is any way I can get YouTube to View my video from the beginning or from the point I want.

Example: When I upload a video to You Tube and its done processing it shows the thumbnail of the video but not from the beginning. I would like to insert a picture and have the You Tube thumbnail of my video show the inserted picture.

Can some1 help

this is very basic dear - just edit the video and overlay the pic at the middle
heres a video I made http://youtube.com/watch?v=mRF99Ig0JP0
and heres the thumbnail that youtube users will see:

its just a 1 second pic