First you need a USB stick to put into your PS2. Take the pics and save them onto it. Plug the USB stick into the computer and go to a website like Imageshack.us. There will be a place to find the pic you want to upload, do that and press 'upload'. A new page will come up with a bunch of codes. Fine the one that's labeled 'thumbnails for forums', copy that and then paste it into a post and you'll have a clickable thumbnail.👍 Hope that explains it.
You don't need to be registered to upload images at Imageshack.us
May I recommend Photobucket (www.photobucket.com). It's easy, simple, let's you upload multiple images at one time and it never suffers from problems like Imageshack tends to have 👍