>Using .NET or any other advanced API...
>
>My goal is to programmatically start Internet Explorer, navigate to a URL, grab a snapshot of the rendered page and save the snapshot as an image file...
>
>Basically, I would like to render an HTML page (HTML / javascript) as an image...
>
>Is there any .NET class of third party I can use to do this? It has to be done in the background, on a server.
>
>Any hint, documentation, links, etc?

See if you can automate SnagIt. This one is a terrific product for capturing any you want in any way you want.

http://www.techsmith.com