If you want them as avatars you will HAVE to scale and make sure they're 100x100, this can be done, keeping quality in a varety of ways. But i will not teach you how to do that for now. "Inkscape" is a great tool for scaling without loosing quality!
First, we start by going to http://www.tinypic.com and click browse:

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Now we browse to the picture we want to upload, and doubble click it:
-No image at the moment-
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