There is a option of uploading a images in picasa and make is available globally. There are chances that google will crawl your global images and make it available.
No That is not correct. If you uploading images to picassa that doesn't take you at googl Image page. Upload your photo at facebook and Twitter it is more beneficial than Picassa.
just add pictures to your site, give them relevant keywords, alt text and so on and they will appear in the image section on google. I get about 20% of my traffic to a website from one such image.
Nope..you can't place your images at Google Images... Google automatically indexed your images.... what you need to do...is put the right keyword as your images name....