My best advice is to be genuine. They'll see right through it if you're not, anyway.
Some kids' games and shows I recommend:
Perplexus
Elenco Snap Circuits(with Lights and Electromagnetism add-ons)
Thames & Kosmos (Motor and Generators, other sets)
Gears! Gears! Gears!
Legos
Lego Mindstorms NXT
LeapFrog LeapReader
LeapFrog LeapPad2
No Stress Chess
Backyard Safari Bug Vaccum
Wowee Paper Jamz Guitars
Rocksmith
Where's Waldo
BBC Earth
Frozen Planet
Arthur
Blue's Clues
Backyardigans
Sid the Science Kid
Bill Nye the Science Guy