Photoshop, Illustrator, Painter are the big 3 that are cross-platform. If you are on Windows you should also look at Xara (www.xara.com)
Wacom tablets are best. I prefer the smaller sizes as your hand doesn’t have to travel as far to cross the screen and they’re more portable. Intuos if you can afford it, Graphire if not.
Jim Kanter,
Digital Film Institute
http://www.dfilminst.com