jGal_Load(5,100,75,20); <--- this line of code can be changed to adjust the size and display of your gallery. The numbers are images shown, width, height, movespeed respectively.
A good demo of how this can be used with lightbox can be seen here: Ligtbox Integration. Click gallery on this page and you will see.
Click here to download the source files
This is free to use. A link back to my blog would be appreciated, but is not required.