You will love it and so will the kids.
the family campervan to the music stages is a bit longer as have to go through all the family camping field and then through the children's area of the arena, but astill not too long.
Loads of things for the.kids to do. A lot are free and my 4yo loved the pond dipping (need to book this), there is also rocket building (get to launch them) and numerous other activities. A few cost such as the old style fairground rides but are £1.50 a person so still good value.
Signing up usually means going to the tent where the activity takes place. will need to do this early as they do get booked out, suggest booking first thing on Friday.
Food definitely, alcohol into the campervan area (no glass allowed) but officially not into the arena though it can be sneaked in!
Best stages depends on what you like. My fave is the sunrise set in the woods, great settign and usually great bands. The Obelisk can get a bit tiresome with all the peopel who station themselves there for the day and chat away, dpends what you want. Good call about the film and Music, it does get busy, also they may turn the children away as have age restrcitions on it, last year a few families got upset when turned away from Lump who were palying in there.
Get there early on the Thuesday and orientate yourself with where the cmpervans are and the entrance ot the festival, arena usually opnes about 5pm and go to go in and wander around to see where everything is. Don't go with preconceived ideas but just enjoy teh experience, try not to have a rigid schedule but chose a couple of must sees each day nd then let the mood take you. Kids can have fun away from the kids area too.