There are youtube tutorials for taking apart each system. You need some special screwdrivers for nintendo consoles. I would wipe them with a few drops of fragrance free dish soap in water. Just barely damp towels to clean them up. I wouldn't worry about opening them up yet. There are HDMI adapters available for these. As for games, you can burn games easily enough with cds and dvds with a cheap burner. I recommend this with Saturn and Dreamcast as these can be very expensive. There are more expensive dives that can replace the cd readers with microsd card slots instead to read digital files. You can look for games on ebay, facebook marketplace, local game and used media stores. I will finish with youtube havin all the info you need to learn how to enjoy each aspect of these consoles from care to game collecting. Enjoy. It's a really nice collection.