I have done some myself and had some done at Costco. When I did my own, I had a projector, a digital video camera that recorded on tape, and a video editor on my home desktop computer. I would project the 8MM onto a screen and set up my video camera on a tripod to record it. After that, I would capture the video into the video editor, edit it, and then burn a DVD.
This is not a simple thing to do. I wouldn't recommend it for many people that I know. Video editing gives you a lot of option: titles, added audio, cutting out bad or unwanted clips, and many other options. The worse problem that I had was in playing the 8MM and recording it. An 8MM projector is sending each frame with a little time lag between frames. When I first tried this, the digital video recording, which had its own frame rate, came out very jumpy. After doing some adjusting on my video camera, I got the jumpiness pretty well smoothed out. Even with this problem improved, I was never very happy with the final product.
This past year, I let Costco, do about 6 of my old Super 8 videos. Overall, I was very pleased with the DVD's. The video quality was much better than what I was able to do myself. They put in a menu and break the video into a number of clips that you can go straight to or you can go through the entire video. They also give you an option to have music added or not. I can't edit it to cut out anything. If I do any more in the future, I will go with Costco.