rob, there's a few ways you can do it. the easiest is to get a photobucket.com account and that will allow you to resize the pictures there.
or you can get a program from the internet, just google: "photo editing program" and look for one that's free. here's one you could try, there's a bunch of other ones: http://www.vicman.net/vcwphoto/
i'm sure someone else will come up with some other methods you could try too.