General: Botswana

Compared with other African countries, Botswana has a lower profile among foreign tourists. Say safari and most people think of Kenya, which means you end up seeing 25 trucks around every lion. Go to Botswana and you may have the whole pride to yourself.
The Botswanan government has tried to encourage lower volume, higher price tourism in an attempt to keep away the flocks of backpackers who add little to the local economy. Yes you can get around independently, but car hire can be expensive and don't expect to turn up at the gates of the gamepark and be able to get in. They only allow a certain number of passes per day, which are mostly pre-booked by organised safari companies.
By car hire I mean 4x4 - there aren't that many tarmac roads in Bots so a four wheel drive is essential.
The official language of the country is English, but indigenous languages vary with geography. The colonialists cared little for local cultures, so when they carved up Africa they artificially separated ethnic groups. Hence the people in Southern Botswana speak Setswana, but those in the north west are the same ethnic group as those in neighbouring Zimbabwe.
The original occupiers of the land of Botswana were the San people, but these have been persecuted over the centuries by other groups and very few survive now. Whatever you do, don't call them Bushmen, which is what you'll find in your old history books and TV programs. They don't like it.
Time for the 'You can't go to **** without seeing ****' bit.
If you see nothing else, see the Okavango Delta. It's the largest inland Delta on Earth and it's totally unique. When you consider that most of Bots is covered by the Kalahari desert, to find something as lush and teeming with life as the Delta is quite incredible. Try to get a trip that includes a few nights camping in the bush. You're not in an organised campsite, but literally in the middle of the bush. You hear the animals walking around your tent at night. Your drinking water comes straight out of the Delta. Go on an early morning game walk and see the fresh lion droppings about 15 feet from your tent when you get back. It's an experience you will never forget.
Our trip included 3 nights on Chiefs Island in the Delta, then a week going up through Savuti, Moremi and Chobe parks before crossing into Zim and seeing Victoria Falls.
Some things I found useful when taking pictures. For a start you need a proper camera, with at least a 300mm lens. (Leave your compact jobbie for snaps around the campsite). If you go on a bush walk you can't get quite as close to animals as you can in a vehicle. Animals don't understand what cars are but they do recognise a human shape and move on before you get too near. Take some form of camera support with you as well. A tripod is a bit too much to cart around but a monopod should work well, or a beanbag for resting your camera on when you're in the vehicle. With everybody else in the truck moving around trying to get a better view, holding your camera steady by hand can be difficult.
Final tip - it's a dry and dusty country. Take a soft brush for your camera, a nail brush for you and plenty of lip salve.