How do I transfer pictures from Picasa 2 to my Sony Memory Stick in my DSC P100 ?

Answer 1

only if the pictures were taken with that camera.
the pictures are in the my pictures folder.
open up my pictures folder and the stick folder
drag and drop

Answer 2

When your camera is connected to the computer via the USB cable, or when the Memory Stick is read via a memory card reader, the computer sees it as a virtual drive.

Use Windows Explorer to copy your Picasa 2 images from My Documents to the Memory Stick.

Answer 3

Haven't used Picassa for a while, but right click and save to stick??