People hate flash because of what it is (flashy) and that it's not streaming and the entire file has to load before it starts playing. Additionally flash isn't read by search engines so HTML on the pages is imperative for good search engine placement. As for actually protecting the images, you can capture them with a screen capture program even if steps have been taken to prevent capture. Face it, if you are paranoid about your images being stolen, don't put them on the web. If you do put them on the web, keep the file size down (pixel dimensions) and add a copyright as a text layer in your image editing program.