I would go with the router too, although I have limited experience with a router so I'm not sure how well it would come out.
On you picture size it does cause us to scroll side to side and it's a fairly easy fix. Just Quote this post and look at the text between the IMG's at the bottom. The width 640 is what you need to add to your picture size to fix the scrolling.
Probably the easiest way to fix it though is to just highlight and copy the entire line below. Then go to your picture post and click Edit. Remove your original picture link and paste the one below in it's place.
Or you can go smaller with a width or 320