Safari park is very good - the boys enjoyed the monkeys climbing all over the car and lions coming so close. Got the impression that could be too busy on a peak day but well worth it if your children like animals.

Great fun but rather expensive. I took my children to a special Noddy day there and was not amused to find out that having paid the entry fee I then had to pay for every attraction in the Noddy area. Not cheap at £1 a 5 minute ride. Still, I made the most of it by taking the children around the Safari Park which they enjoyed.

I love Longleat. It's probably my favourite day out and I have a couple of top tips to share.
Firstly, most people tend to go to the safari park first so it's usually really busy. Everyone then rushes to the safari boats and the queues are ridiculous. You can expect to wait an hour or more on busy days - not good fun with small children!
My advice would be to go straight to the safari boats to feed the sea lions, (adorable!), do all the other attractions you fancy, then head to the safari park about an hour and a half before you want to go home. You won't have to queue for the boats and you'll pretty much have the safari park to yourself. Also, late in the day, the animals are much more active - they're on the prowl because they know feeding time is coming. If you're lucky you might even see the monkeys being fed - great fun... they go bananas, (geddit?)
(Note: It's quite a drive from the other attractions to the safari park, so check what time the park is closing, (it varies!) and make sure you allow plenty of time for the drive.)
My other little tip is to encourage your children to try to win a Blue Peter badge and they'll get in free.
And not just to Longleat... they'll get free entry to lots more places such as zoos, aquariums, castles - even Legoland. Take a look at the Blue Peter website for ideas of how they can win one.