2015-10: If existing users have had trouble logging in or posting, this should now be fixed. Sorry! --Morbus.
It entirely depends on who is on the island with me.
Cards are the most versatile. You can play many gaves (even RPGs) with just a deck of cards. With a greater likelyhood of finding people who enjoy cards, this would be the safe bet. Cards are social and reach across the gender gap. Cards wear out relatively quickly though, and likely wouldn't last beyond the first year.
Chess would be a poor choice for many reasons. First, you aren't likely to find many people to play with you. Second, the game only involves two people. Third, it gets tiring playing the same people all the time you are either the perrennial winner or loser. Things may fall into a rut.
Computer games -- well, assuming that I have an unlimited power supply it works okay. But if I'm running a Windows-based operating system I know I'm going to need to re-install the OS every 5 years at the minimum. Will I have all the disks to do this? When will the power supply kick out. I bet I blow a component within 5 years. In the meanwhile, the game has made me lazy so I can't run away from the man-eating lizards. Again, a bad choice -- I'll pass on the computers.
Role-playing game. I'll almost take this one just to get at the dice. Dice take a really long time to wear out and are one of the few game elements with even a chance of outlasting you. Even worn out they work relatively well. The rulebooks I can use to start fires once I have them committed to memory. If it is one of those games with too many rules to remember I can just burn it out of spite. I can use the pretty pictures to decorate my shack. This is not a bad choice, although I still have to find someone to play it with me.
Twister. You can use the mat as a shelter, raincoat, or sail. The spinner could be used for other improptu games, but there's just not a lot in the box. The oil could be used to start fires (you get a bottle of body oil in the Twister box, right?).
Monopoly. Hotels, money, dice, figures, cards, and a board. Hmm... Stuck on a desert island you could make turn the chance cards into playing cards, do something different with the community chest, make an rpg (you've got dice and figures), and play monopoly. Turn the board over and you could use the houses to play other games. Risk has possibilities too.
I'd find the most complicated board game I could, one with lots of figures, and make as many games out of it as possible. Does anyone know any board games that include both a deck of cards and some dice? Is that cheating?
Yes, I'm fairly certain this is cheating, but kudos for deep thinking. You certainly went a lot farther than I did...
Ain't the island supposed to be desert? As if, with no one but you there? I find hard to play RPG all by myself.
Is it a desert island? a region so arid because of little rainfall that it supports only sparse and widely spaced vegetation or no vegetation at all
or a deserted island? untenanted: without inhabitants
The first indicates that there MAY be others to game with, in which case RPG is my winner and sounds like a rather pleasant existance, assuming food and drink are available.
In the case of the second: I'm inclined to go with computer and select a MMORPG with the chance of getting someones attention regarding my plight, or assuming that plan is a cheat, at least I can play solo games, though solitare is going to get old.