I can't upload pictures??

Whenever I try the one requiring flash, it says "Error 422", when I try the old one, it says "error 500". I have the newest version of flash... I'm using a macbook pro... I don't know if that contributes at all... Help? :(

Flash runs fine on OSX. It's only iOS products that don't run flash. ((And for good reason, flash is shit; It inefficiently eats up battery, it's proprietary, and it's not designed for use on touch-screen mobile devices.)) That said the site should really kill the flash and classic uploaders and just switch to using native browser features. A file input, enhanced with JS when supported. Browsers already have native support for everything you need to make a fancy uploader. File selection, multiple file upload, ajax uploading with upload progress events, and even file drag and drop support to create drag and drop uploading with. There's no reason something as shitty as Flash is needed anymore for file uploading.

i had the same problem and i did print screen shot of that photo, pasted it to program 'paint' saved it and then the size of the picture was smaller and it worked when i wanted to upload it on the site

That's an absolutely horrible, horrible way to resize a photo. But it sounds like you're running into the file upload size limit but the system isn't setup to give you back a proper error message for that case. Well, not that this site is properly coded to tell you what you've done wrong in practically any case.