httrack is a good program for downloading websites. Remember to change the downloadspeed so that it downloads stuff faster it is set by default to 2-4 kb/s. There are many options in the program, you can for example configure it to not download thumbnails by make it not download files smaller than 10kb.
Anyway, if you want a program that can download pictures that are thumbnailed on a forum or a page and that are linked with a php script to the full image I'm also looking for a program that can handle that.
I have tried some website rippers and the best is always winhttrack, or simply saving the individual page in explorer if you only want a single page, but I would like other advice.