Small Pictures

Is there a way to post pictures and have them displayed like the old website did. All the pictures I've posted lately are pretty small, then when you click on them to enlarge them, they only get slightly larger. The old site would display them almost as big as the screen.

Actually... the old site only allowed for 640x480 pictures... the new site allows for 800x600. I think the difference is in how its presented to you.

How can I change it, or is something in the site itself? It's kinda a waste of time posting pictures, when you can see any detail in them from the size that they show up.