My 2-yr-old son loves: (Outdoors) his tricycle, and (Indoors) his Rody bouncy horse (inflatable and he rides on it).
My 5-yr-old son loves: (Outdoors) his bicycle, and tools to pretend he's working (hammers nails into wood, etc.); (Indoors) he loves Wedgits & Legos, his train table and track, and also fingerpaints constantly.
They both love their small trampoline for outdoors, also. We got the kind that has a padded handlebar for them, so even the little one can jump pretty safely.
Her favorite activity is board games. All day long she asks to play games with us (I have a post about this). Although she is getting a DS for her birthday so that may become a tie with board games, or a close second for her. She will be 5 in 2 weeks! She is an odd kid though, she loves having me write quotes for her to copy in her copybook too and she likes reading me her BOB books. Oh and she likes playing on her Nook and reading books on there as well.
Mine are 5 and 7. They love to skate. I have one that is wanting to try speed skating and one that wants to figure skate on roller skates. We are going to try to figure out how to indulge both of them without breaking the bank.