If you have a digital camera, the software that was bundled with the camera should be able to perform the compression and resizing for you.
If not, Microsoft's Office Picture Manager is bundled (FREE) with many Office Suites and is more than sufficient for hobbiest to compress a few pictures to share with friends on this forum.
Picture size (quality) is not as critical for web viewing as many people suspect.
A while back I downloaded some pics from a friends vacation. The 75kb pics were fine for webviewing. No, the 75kb was not as detailed as the 6mb pics that he forgot to compress before sending them to me, but all in all, I would rather see a 75kb pic of his wife than the 6mb pic.
By the way I am using a 19" LCD screen.