If the images are too large you can adjust that by editing the image tag. Look at what you typed in for the image address. It probably looks something like this:
[img]http://larry-brickman-1972.memory-of.com/Uploads/Pictures/2006/4/20/SlideShowPic632811653767500000.jpg[/img]
Now notice that the very first part of this is
[/code]
Notice that the image needs to stay in a similar ratio of height and width. When you have a square picture could use 50x50 or 300x300. If you have a rectangle that is 100x300 you could stay with the same ratio by changing it to something like 200x600.
I'm sorry if this is all confusing to you. Not to worry. Just experiment and see how it works!