You sound just like me! I have a 2 and 4 year old and a husband that works and a 5 year old dog.
Here's what I do: I adopted flylady's cleaning habit of making sure the kitchen is clean when I go to bed. I do not want to be faced with a sink full of dishes first thing in the morning! This is hard to do when I'm finished in the kitchen at dinner, but hubby goes in there to get a snack before bedtime. Just a quick look-see before I go to bed and it makes me a happier camper in the morning. ha!
Second, I spend about 30 minutes (max) each morning picking up clutter around the house. Our hots spots are the counter tops in the kitchen. I put stuff away (everything should have its own place - if it doesn't, designate a space for it), throw away, gather up magazines, put away toys, etc. If it's not done in 1/2 hour, it's OK!
Third, I am not afraid to get rid of stuff we aren't using. We have a garage sale once a year in the spring. I also take stuff to Goodwill ocassionally, or sell it on craigslist or Ebay. This could be toys, books, exercise equipment, or just "stuff" that is unused in your house! Every few months I also take a stack of magazines to my kids preschool. They love to receive them 'cause the kids cut them up for crafts. You won't get anything for them at 1/2 Price Book Store, and this way at least you're recycling for a good cause.
Fourth, I try to involve my kids with cleaning. With your five year old, you could do this. I do it with my 2 and 4 year old and they love it! I set the timer for 10 minutes and we "race" to see if we can have the room picked up of toys before it buzzes. The other day I put socks on their hands and let them dust the living room -- they LOVED it! They were doing baseboards and everything! LOL And they ASKED to do it the next day! But I wouldn't go overboard on that so the newness won't wear off. ha! But I also have them take toys, books or shoes back to their room where it belongs, or help me match socks when I take a load of clothes from the dryer, etc. Any little thing I can do to have them be invovled keeps them occupied (at the very least) so I can finish the task and it also makes them feel helpful.
Don't stress too much. Even for all of this, my house can sometimes look like a clutter zone! Phyllis Diller was the one that said, "trying to clean house while your kids are young is like trying to shovel the sidewalk while it's still snowing!" LOL
Good luck!
L.