Discus aren't as hard to look after as everyone makes out, in fact they're easier than rams in my experience.
I suppose the first thing to check would be how suitable your water is, as typically discus like water that's neutral to slightly acid (6.5 has always worked for my discus) and quite soft, so do a pH test on some tap water and have a look, if you can't test the hardness of your water generally your local waterboard can tell you. My tap-water is dead-on 7, but the driftwood in my tank (plus some peat in the filter) kept the water around 6.5 and that lovely tannin-colour, which they appreciate being from the Rio Negro.
Apart from that, just keep up on water changes. I remember a while back on here someone posted their advice on keeping discus which went something like "water change, water change, water change. Here, now you're an expert discus keeper", which, surprisingly, is really true. One waterchange a week is sufficient to keep them healthy and happy. They don't like the light too bright, so cover from plants is always appreciated. Good filtration is a must to keep up water quality or they can be susceptible to hole-in-the-head, which, although easily treatable, is a sure sign that your water isn't good enough quality. Parameters should also be tested regularly and rectified where appropriate.
Discus are quite social fish, so more than one is IMO essential. However, as with angels, keep them in even numbers, as if pairs form and one's left out, it will be bullied almost relentlessly around breeding time.
Food-wise, frozen meat-based foods are best, there are special discus preparations about which my discus always went mad for, they also love frozen bloodworm and beefheart. I've also found discus aren't fussy, and will often eat the flakes you feed your other fish (although, it's not advisable to feed them just on this).
They're often also not as expensive as people think. Varieties which are relatively common such as red turquoise and blue diamond generally don't cost the earth. None of the discus I bought ever cost over £15 in British money.. around $25 I think.
If you have space, I say go for it, get a pair, they're fun, personable and extremely attractive fish and really not as hard to look after as people make out. I'd liken them to koi for the tropical tank.. clean water is a must for health and happiness.