I can't believe I know so much about this...
I've found that if you learn the secret for any particular plant -- then it isn't so tough. Ficus are tempermental -- but if you water them a lot, make sure they get bright direct sunlight, and you feed them every 2 weeks -- then they do well.
African violets are hard, IMO. They need very direct sunlight in order to bloom. And they need plant food regularly. They must be watered from the bottom -- the water damages the leaves. And they like to dry out pretty well between waterings. There is a special kind of pot they like -- it is 2 pieces. You put the water in the bottom part and it drinks as it needs too. Otherwise, make sure the pot it is in has holes in the bottom to allow for good drainage.
Cactus need bright direct sunlight. Food and water about once a month.
Peacelillies are easy -- if they are kept in low light and watered constantly. You can put a tray or saucer under a pot with holes in it, and fill the saucer with water to let it drink constantly. People actually plant these in fish bowls, completely submerged, and let the fish feed on them. They cannot be overwatered -- which is nice, I think. Worrying about overwatering can be more stressfull than forgetting to water, for me. antheriums are similar in temperment, but come in pink and purple. I like that they flower year 'round. Rembember -- low light.
Pothos and philodendrum are very good ones too. They bounce back if they are damaged. My dog ate our philo down to nubs sticking out of the dirt, and it grew back and is once again gorgeous. Funny thing too, because they are supposed to be highly poisonous. But the dog is okay.
Spider plants and ivey are pretty easy too -- they don't want direct light though, and they like damp soil and mist on the leaves.
Tropical plants - palms especially - can be really difficult to care for. I avoid them because I kill them. Though rubber plants are pretty good.
I've been working at Home Depot for six months -- and was soley in charge of the houseplant are for most of that time. I didn't know a thing when I started, but I am finding it easy to pick up and I enjoy it. Home Depot carries a thin magazine/booklet about houseplants. It is .98 cents. The info is straight forward and simple. I recommend it!
Editing to add -- HD guarentees houseplants for a year. Save your receipt and bring it back if you accidentally kill it. That way, you can try another one without racking up bills!!