Hearts is a 4 player game, and in this case 3 of them are AI, and actually quite fast based on the program size. This game
does require a lot of RAM, and I wouldn't recommend it for the TI-83's (even though it's fine on the SE). The rules are basically the same as for the hearts game on Windows XP. This game also includes all the rules. You can read the hearts game instructions by going to Start Menu -> All Programs -> Games -> Hearts -> Help -> Help Topics. (on Windows XP).
To select a card, press a number 1-9 or [,]=10 [(]=11 [)]=12 and [sin(]=13. Press the number above the card to select it. The cards are displayed in a format like C5, where the 1st character is the suite and the 2nd one the number. For suites, C=Clubs, S=Spades, D=Diamonds, and H=Hearts. The first player has to put down C2 (or 2 of clubs). For the numbers, instead of a number there can be a J (Jack), Q (Queen), K (King), A (Ace), or X (10).
You need to have the programs SHUFFLE and HEARTSX in RAM to play.
L5 stores the score info for each game and is reset each time you play, so if you want to play the real way to 100, you can write the scores down for each game and then add. You're player 1 (your score is the first element in L5).
Enjoy!