We love Jumps and Jiggles! Pirates Cove next door is also amazing when it's open.I have the best indoor playspace for you! It's called Jumps and Jiggles in Elk Grove Village (their park district). The large, clean, friendly-staffed place has a large tube play area (like a clean, glorified McDonald's playspace) with smaller younger child play toys in the same space so you don't need to run around checking on two kids.
Now, here's the best part, the adjacent room has an indoor carousel! Not like the dinky mall type - a real, large carousel. Last winter my kids were just 2 and LOVED it.
Wait, there's more! It only costs $3.50/child, no cost for adults, and you can get a 2 for 1 coupon (see link below) and ample parking is free!
If you can't tell, I absolutely love this place. I can't wait to take the kids again this year.