Usually any outdoor space tends to be called a garden, even if it's completely concreted over and is really just a patio. You did say yard, but that often tends to imply something more industrial than domestic. The floors are probably laminate, not hardwood, but if all you really means is 'not carpeted', that is easier. It's still very common to have mostly carpets here though (sometimes even in the bathroom!), so if you're willing to be flexible on flooring, you'll have an easier time.
No, they won't leave their family photos, but sometimes there will be some decoration left on the walls depending on the landlord. I would expect the bare furniture and probably curtains and light fixtures to stay, but not bedding or stuff that belongs to the current residents. When you view a place or contact an estate agent they'll tell you exactly what is included, and there is usually some negotiation allowed, e.g. if you wanted to have your own mattress or something. It depends on the specific landlord. You'll probably be expected to have contents insurance that covers your landlord's furniture.
