I always suggest that if it is your first time and you are trying to do all the parks, do them in build order.
MK, Epcot, MGM, AK. My reasoning is that the technology improved at each park. If you start at MGM then go to MK you may be dissapointed.
Also as stated by others, slow down! You will enjoy it better if you miss somethings and plan your next trip.
Let me say it this way. Since getting married to DW in 1980, we have been over 45 times. DS, 20 has been over 40 times. We went for a week in March, and we dedicated the week to things we had not done before, or in at least 5yrs. You will not scratch the surface in 4 days!
We also have everyone pick a particular thing they want to do. Make sure you do those things early so you can do again if you want to.
Some of the things you will do will be based upon your kids ages. We do not go to toontown often with a 20 yr old!
Take a deep breath and have a wonderful time.
Oh, and be careful!!!! Pixie Dust may hit you and you will get the dreaded WDW withdrawl!