Great idea, great gameplay make this oldie a goodie.
The graphics are, obviously , old compared to the graphics of today. Block stick-figure like people, and blocky buildings are the norm in this game. The helicopters are rendered rather well compared to the rest of the game. I've never had frame-rate problems with this game, even back when I had a bargain bin bottom-line PC.
The sound in the game isn't too bad. You get the rotor noise continuously, but this is to be expected. You hear rushing water when flying over water, car horns and such when driving over the city, and even the occasional crackle and sizzle if you fly into a fire. The music selection, and the stations, are very well composed, and the news/commercials lean on the hilarious side.
The controls were the one thing I had a problem getting used to, since I had small hands back when the game came out. While I eventually sucked up and bought a joystick, the keyboard controls are logical and well laid out. The mouse can be used (as well as certain keyboard keys) to control the various equipment you can acquire for your helicopters.
The gameplay itself revolves around doing randomly generated missions of varying difficulty in a number of different cities. These missions range from breaking up simple traffic jams to quelling riots and rescuing people off of runaway trains. Since you typically never know what comes next, the game tends to keep you on your toes. You could be a firefighter one minute, a paramedic the next, and then go into law enforcement. All in three to four minutes.
All in all, if you can get your hands on this game, do so. Its a fun, stupidly addictive game. The added bonus of being able to fly in *any* city you build in SC2K means theoretically an infinite amount of possibilities.