need direction on using desktop background image to fill 3d

Hello, new to the forum and 3d creation in general but was hoping for some insight or direction on something. I'll try not to make this too long but here's my question. I have the cyberbuddy msagent desktop character program on my computer and have created my own simple characters but want to pursue something I think would be cool. If you've ever seen the movie Fatal Error you know what I'm talking about when I say I want to have a character that is nothing more than a face that appears on the screen but it's kind of a 3d face with the color/texture being whatever the background happens to be. That is when the character made itself present it would appear as a 3d face kind of morphed into whatever your screen happened to be. Now I realize there are multiple issues to deal with here but any insight or advice on any aspect of wrapping an image over another image while maintaining a 3d look would be appreciated and might help me get started. It would also need to be capable of animation and not just static as the face and mouth would need to move. At this point I'm not sure if it's something that can be done with flash or if it's not even possible. I'm really kind of a newbie to all this and I'm sure most with experience with something like this will have more questions than answers for me but I gotta start somewhere. I only have PSP and squirlzmorph right now and they don't really seem to be able to help much but I need to know what software I would need. Thanks for taking the time to consider this.