There are several ways to make them smaller on a laptop.
MS Paint will do it.
If you have several, there's a free program called irfanview which is good. Also a simple photoshop-a-like called GIMP.
Or just upload them to an image host like flickr or imgur. They even give you the bbcode to paste it in to a topic. The forum resizes it after that and it doesn't use any of our bandwidth.