Replies to post #63481 on The Question and Answer Board (IHUB)

[occams_razor]

jpg. It uses lossy compression, is the most efficient in terms of data size, and is the most easily resized.

[XV19]

save them as JPG.s they're usually the smallest, and if you're main goal is to post screen shots up to here, that's a good way to go.

I usually resize to 640 x 480, just so people online don't complain :)