7, 4, and 1 year old boys. 7 year old's legos can come out when little ones are sleeping or anytime he wants to play with them in the basement. Any I find on the floor in areas his brothers play are immediately trashed. This has worked well the last 2 years. Magnatiles are also great, although PP is right that the younger ones will easily destroy creations.

Imaginext, playmobil ...

My kids are 3 years apart, and the 5 year old just started with legos this christmas. My two year old doesn't put anything in his mouth, so I don't worry about that. What has been a challenge is the little guy will break the older guy's creations. I can't really segregate them that much since the little guy will only take a nap once in a while, but we try to keep things intact for a day or two and then its a lesson in rebuilding...

I have an almost four year old with an 18 month brother. We got the real, big-kid Legos for the older one for Christmas. He is only just ready for them, but loves to do them with us helping. We have them in a special box and he knows we can only use them when his brother is sleeping.

Magnatiles are perfect. We put off the lego purchase for the same reason. And our younger one can also mild with magnatiles but legos would be impossible

Our five year old with a two year old sibling has legos which must stay in his room and magnatiles as well. He loves them both. Magnatiles would be a great idea--though little sibling may love to come smash the five year old's creations. You really need some way to separate the two of them so your older one can have some more complex play.

I haven't bought Legos yet for my 5yo because 2yo is always around and would want to play with them.

Are there any other building toys that would be fun for a 5yo and easier to share with a 2yo - maybe something with bigger pieces but more grown up than Duplos? Would Magnatiles or anything else be more fun/easier to keep organized with a little sibling? Or should I just get Legos?