Photoshop - 3 comedy scenarios

Hi - I have an employee in my Organisation who is celebrating 10years service with me. I have only 2-3 head photos of her - but wanted to do something 'comedy' as a presentation for her.

I would like to have her head photoshopped onto i) a formal picture of someone meeting the Queen (of England) ii) a formal picture of her meeting Barack Obama and iii) a picture of her meeting Kim Il Sung.

Can you help? Photos will be dropped into a presentation.