I would suggest the PiStorm32 for the A1200, will do everything you want, or if you after the classic feel, TF1230, 8Gb CF card. Video you have options of a scandoubler like the indivision Mk3, or RGB to scart to HDMI.
A500 again PiStorm or a TF536 and a RGB2HDMI, there are lots of options for all budgets! lol