The white interior of Le Creuset is designed to allow you to see how much browning is going on, when you are cooking meat or veggies or making a sauce. Black interiors make it harder to see what's going on with the food.
The handles of some of my pan lids are plastic, others are metal. I use both in the oven at temperatures up to and possibly over 500*. The food doesn't touch the pan lid, so I don't worry about plastic in the food.
The two pans that I use most often are the dutch oven and the lidded casserole--a round, shallow pan that's useful for browning meat, braising food, and making risotto. I also have two nifty pans that are saucepans with a frying pan for a lid. They're useful, but if I had to choose just two pans to buy, I'd skip the saucepans.
I also have two cast iron skillets--one is an enameled pan, the other not. Both work interchangeably, so if I were trying to save money, I'd get a Lodge cast iron pan, season it correctly, and get used to cleaning it with kosher salt and a paper towel, then hot water and never dish soap.
If you have an outlet mall near you, look to see if there's a Le Creuset outlet in it. Besides selling a full line of this year's colors, they usually also have some discontinued colors and may offer factory seconds on other pans. Resist the urge to purchase stoneware bakeware in matching colors; the prices are high, and the performance no better than standard pyrex bakeware.
The prices of Le Creuset is high, but if you take any sort of reasonable care with the pans, your grandchildren will be using them someday. (Possibly because you have become too weak to lift them!
). They last and last, and I really do use mine every day.