Pirates! is simply incredibly fun.
Bad: Slightly repetitive by nature.
Sid Meier's Pirates! is, like seemingly everything with Sid Meier's name on it, incredibly addictive. It's also highly polished and fairly simple by today's standards of big-budget, epic-scoped, and gritty shooters and the like. However Pirates! shows there's something to be said for planning something simple and doing it exactly right. Additionally, Pirates! show's that just because the basic elements of something don't necessarily have to be complex or incredibly difficult to understand, it doesn't mean that it lacks sophistication.
Pirates! is, at it's core, a series of minigames, loosely tied together by the interespersed time you spend sailing your ship at sea and the premise that you're a pirate, and you can do what you want. The game has a loose storyline that sets off the premise, which is mainly something about losing your family, and now you're out to find them. It's fairly weak, and as soon as you get out to sea - minutes into the game - you can choose to pursue it, or totally ignore it. There's no real story-line. Do what you want.
Pirates! doesn't envision the life of a pirate as the probably unpleasant and gritty affair it was in real life, but as the swashbuckling affair that it was imagined to be, so you play a charming rogue. Sure, you can attack any ship you want to on the open sea, but you can also romance governor's daughters, find buried treasure, attack cities with your crew, and engage in swordfights with wily captains. Nearly the entire game can be played with the numpad keys, but it doesn't mean that each minigame isn't a ton of fun. They rope you along in an addictive manner, but it also means that Pirates! can be played in short or long streaks, and still be very fun.
The presentation reflects the attitude to the gameplay. The graphics are charming and colorful and still hold up fairly well today, and the music fits as well, though you'll get familiar with many of the themes.
Pirates! is a one-of-a-kind game these days. It doesn't mess with the success of the original, but ends up being completely unique. Whether or not you've played that one (I personally haven't), you won't go wrong with Pirates!.