That seems fine to me. It is only 640x480 or so. More than suitable for the boards. Did you want it in your signature or something? Then it has to be alot smaller. I have no idea how to make photos that small and still look good. I'm looking for that answer myself.
Do you have any photo editing software? If not there are some great programs that are free like GIMP. Or you could spend $50-100 on photoshop elements or paint shop pro. Or many hundreds on a full photoshop program.
I host my pictures at www.smugmug.com. I send a very large file. I then have the option to choose what size I want to post. Everything from a tiny thumbnail to the original file size.
you can also get a small programs that just resize pictures, but I don't remember the names.