If you go the Wii route though, you'll soon hate the aiming. I've beat that pretty good Ghost Squad, the crap and not child appropriate (based on language) HotD: Overkill and the first Nerf game all recently on my Wii, using the Nyko accessories benstylus mentions, and it wasn't great.
That said, you will need a CRT for anything older, like the
or
versions of HotD or a PC setup and something like the Synden guns.