OK, you get the little bundle of joy home. The kid starts to eat. The kid starts to get big. Time flies. Now he's 24 months, which is parentspeak for 2 years old. He's taken every one of your albums out of their jackets and put a whole new set of grooves into them. The dog loves the kid, because anything the kid gets to eat ends up on the floor, and having a dog around is an easy way to keep the floors clean. Your cat, however, has moved out. The VCR won't work. You find out it has a 2-day-old piece of French toast jammed deep inside. But that's OK. You haven't been able to watch a movie all the way through in some time. In fact, you've developed a system in which you watch part of it one night, then get up early the next morning, before the little darling awakens, to see how it turns out. Which means you have to get up about 5:30. Your naps are a thing of the past. At the end of a busy day you curl up in bed with Reader's Digest, because "I Am Joe's Liver" is about as much as you can comprehend right now. Maybe you're reading this in the kitchen. You're trying to figure out where to take the little one during the week. Maybe, for some insane reason, you've taken time off from work to spend quality time at home. Last night, after the wife found your mortgage records floating in the toilet bowl, you had a very good idea where you wanted to take your kid. But that was last night. Wouldn't it be great to bring him somewhere, get him moving, get him exhausted so he'll conk out as soon as his tiny noggin hits the car seat? This is your chance to tell him what your dad used to tell you every day for 20-odd years: Take a hike. Actually, you'll be there too, because the Palisades-Malibu YMCA is sponsoring a nature walk through Temescal Canyon for parents and children ages 2 months to 3 years at 10 a.m. Wednesday. Reservations are required. Call (213) 964-3955. A donation is requested.