K.C.
If you want something to keep the younger one active, look into children's gyms near you. Here we have Gymboree, My Gym and Little Gym as the big chains. Maybe you have one, too? A membership to something like that might be great for him.
For the older one, some Leapster games or cool cars would be great. My 4 year old asked for an ambulance this year, so I got him a neat Playmobile one that opens up in back and has a stretcher, plus some other equipment.
I also hope you'll check out my Discovery Toys page. We have some really great toys and games for toddlers and preschoolers (and really, kids of all ages). You can see it at http://www.discoverytoyslink.com/karenchao My favorite toy, Motor Works, is currently on backorder but will be available the week of 12/5 and will ship in time for the holidays. It's our #1 seller and a huge favorite among 4 year old boys.
Happy holidays!