Photoshop!!!
But, Kodak, ImageServer, Photobucket, Flicker, MS-Page, MS-Image, will all permit you edit photo size. (Even check out the ancient "Bandwidth Conservancy")
For "web-page" publication a 72 by 72 will give the reader all the pixels most traditional screens can display.
What is your purpose????...that determines application.
Sincerely,
Gargoyleyou can even drag/draw to fit format....if loading speed is not a consideration.