1.Yeah, when I said "Big Image" I didn't mean extremely big, but I can paste small things.
2. It says I have 2.6 GB In Use, with 3.1 GB Available.
I've never been the best with stuff like this, but if I have 3.1 GB available then I should have enough memory to paste something that's 520x260, right? It makes no sense.
EDIT: Woah, so I tried pasting something 2000x1502 and it worked, so I went back and tried to paste my original image, it came up with the same message. Then I tried pasting an image that was 1200x1200, and it worked. Then I went and found another image that was 620x430 and it came up with the message again. I don't understand how this is happening but hopefully you can work with this information.
Thanks for the help!