If you are looking for learning design theory then that is a separate issue to learning the skills required to make that vision a reality in a piece of software. There is a pretty good cross over of skills between Photoshop and Illustrator and Fireworks.
At its heart the programs are really just doing 2 things. Creating content using pixels or vectors and then manipulating those shapes or pixels to create different mixes. It sounds like you aren't looking for the skills so much as the design theory side of things. If that is the case I'd recommend heading down Ralph's suggestion route for learning. Find a tutorial on a particular effect or design that you like the look of and then learn how it is put together.
Flash is a different beast though. I'd tackle this part differently if you haven't had any exposure to it before. Start with the basics on this one and build your way up.
Lynda.com will teach. I've watched numerous tutorials from Lynda, that's how I became good with Photoshop & Illustrator. If you are using the selection tool for cutting and many other tasks in photoshop, I recommend watching a Lynda.com introduction of photoshop series you will gain or atleast I hope you will gain valuable information. If Lynda.com is not your style of learning do a search for other photoshop training there is a vast amount of tutorials both free and paid online.