Okay, a brief lesson in oils:
Most oils are basically the same, some are mineral based, some synthetic, some a mixture of the two (semi-synthetic)
Nearly all new cars run synthetic or semi synthetic blends. Mineral based oils re primarily used for older engines now.
Viscosity is the key.
Viscosity (how thick the oil is) is the key to oil choice. Get an oil that's too thick and you're putting extra pressure on engine parts, get one too thin and its seep past rings, out of gaskets etc etc.
How do you know how thick an oil is? You'll notice there is two numbers to an oil. eg. 15W-50
The first number is a cold viscosity, the second an 'operating temperature' viscosity.
The LOWER the number, the thinner the oil.
A racing oil, synthetic, could be 0W-10 or 5W-10, which are thin and designed for that useage.
An old clunker of a car that blows smoke and east oil would better off using something like a 40W-70. Thick as syrup!
For cars like ours, I recommend a 15W40 or a 10W40 for everyday driving (if you live in the cold cold states, maybe think about a 10W30)
Now, to brand choice.
From 10 years in the car parts industry I have seen a lot and heard a lot about oils. What's good? What's bad? This one is sludgy etc etc. (which by the way, most 'sludgyness' comes from poor oil choice).
Big brands like Penrite, Mobil and Castrol have always been a consistent performer. These would be my choices, unless you can get your hands on Fuchs or Titan oils.
The other thing you need to be wary of: oil additives.
Wynns, Nulon etc make lots of stuff to add to your oil for better performance, protection etc but a lot of these contain additives that clog your oil filter etc.
Be careful what you add to your engine as oils are one of the most overlooked 'necessities' by car owners.
Hope that helps a little