Oooh a subject close to my heart! My dad got me some chickens when I was about 12 and I continued keeping chickens as pets until I left to go to university. They are absolutely fantastic and easy to tame, especially is you get them young. I had a few from chicks who would follow me like a dog. And all our chickens would come into the house (they climbed our back stairs themselves) and sometimes sit and watch TV with us in the evening. They also enjoyed raiding the dog's bowl for food (he'd watch meekly from a distance), and jumping into the sink in case we were washing lettuce (one of their favourite treats). We had lovely big free range eggs, and bantam eggs too, and apart from those perks the hens were all real characters and brilliant fun.
Chickens are pretty easy to keep IMO. You'll need a good secure hen hut for them as you're virtually guaranteed a visit from your local foxes, secure catches, solid doors and wire, also beware of them digging underneath. Also bear in mind that it's virtually impossible to fully protect chickens from foxes; we had no trouble for years but eventually lost our last two hens to a daylight fox raid - ie while the hens were free ranging in the garden - and this was in a residential area; clearly the foxes didn't care about being spotted.
You'll need to decide whether you want just hens or hens and cockerels. If you get cockerels you will get woken up at 5/6 am, maybe even earlier in summer. They can also be territorial and will fight with other cockerels, and you only need one to several hens. We used to buy ours by auction from the local cattle market, but we also got them out of the local ads paper, and from our local rare breeds farm (they had a few mixed breeds they didn't want, which we got for free). Markets are good for a bit of variety eg we got a couple of ex-battery hen to whom we gave a nice retirement, also a Malay game bird on one occasion who was one of our favourites. We got our hen hut from a local ads paper too and it lasted years, in fact once we didn't have hens any more we handed it on to friends who had decided to get chickens.
If you're out in the stix you've probably got mice anyway, we had to be really careful not to encourage any because we had chickens in our back yard in close proximity to the neighbours and if they didn't like us keeping hens, they could have kicked up a fuss. You get chicken feed from animal food retailers (mixed seed and grit is the basic diet; ours had a hot meal every day (! - this is not necessary) of rice, cereal and our scraps. It's best to feed in feeders but it's also good for hens to scratch around for their meals as that's what they naturally do.
It's all good fun really, just be aware that you have to keep them cleaned out regularly, fresh water is a must (this might involve some cold mornings breaking ice and replenishing in winter), and of course chickens can cause silly-money vet bills when they get sick, like any animal. They will also eat your plants and flowers if you let them roam indiscrimately. I think they're great for kids though as a child can feed them out of his hand, help with the cleaning and care, and chickens are fast enough to run away from a toddler when needs be too! I'd say go for it, I'm going to get chickens again as soon as I've got the right kind of place for it )