Visa info etc

I am a British citizen planning to move back to the UK with my Canadian husband and 2 toddlers (born in Canada). Can you tell me where I can obtain the UK Ancestry Visa application form as my husbands' grandfather was born in the UK. I looked on a couple sites but could find no downloads. Is it something I have to apply for online? Also, what, if any, special Visas do my kids need to live and go to school in England? Any suggestions for moving companies? We won't be moving much furniture; I'm thinking maybe a crate? And to add to it all we have a much loved 100lb pooch who needs to come. Any one had experience moving the family pet to England?

Thanks so much for your advice and any other suggestions you may have for moving a family overseas would be greatly appreciated.