We've stayed down the block at the Alpine, that was about 3 years ago.. it was inexpensive and CLEAN (a big deal with us) and the noise level wasn't bad. if it's still the same, then it was well worth it and too, was walking distance to the park..
additionally, those hotels directly across from the park are VERY used , dirty and loud.. that has been my experience... so although they are close, if you stay there BEWARE................ also, there are restaurants along that strip across from the park, one of which is Denny's.. IF you eat out, then get there EARLY... before the crowds.. e.g. park opens at 8am... then be at the Denny's before 7am.. (pref 6ish) otherwise, there is a long line... and that will delay you from getting to the park...
Bring snacks/water with you in the park, this way you don't have to find food right away in the park.... like some of the novices :) also, if you need a locker, get one asap........... then, go directly to the kiddie rides (they fill up early) because like you, people want to get their small children on them before nap time.. by noonish, you ll begin to notice many strollers parked with sleepy kids..
oh and if you stay for the parade, stake out your seat EARLY.. people start lining up on Main street at min an hour beforehand.. to get good seats... and bare in mind, if they do fireworks... I have been there when they closed off the kiddie section. so if you think you will be riding rides at night, ask an employee which part of the park will be roped off...
Umm what other good advice... San Diego Zoo... it's BIG.. so go early before the heat .. this way, it's more enjoyable. the Pandas are VERY popular... go there first... otherwise, a line will build.... have your map in hand..... many turns in that park... you can lose your way... the bus is a good way to tour it... but sometimes it's a pain in the neck dealing with the lines in which to board... again, go early............ The park is deceiving, while it does offer much shade... it can get HOT.............. and there are some inclines to walk up... which when you are hot and tired can seem like a lot , especially with small children...
Oh and while in San Diego,if you visit Little Italy.. don't be swayed by all those Italian restaurants.. they are pricey and frankly, I wasn't too pleased with the food... However, right down the street was the burger lounge... YUM.... great hambuger, good fries, choice of salad if you want to go light.. and the service was quick and friendly.. as for OLD TOWN.. Good scenery... but food not too great.. Mexican Restaurants for which I wasn't impressed..... burger lounge was much better. oh and good shakes there as well...
have fun!!