Imagine you are stuck on a deserted island with no electricity, alone. You find a magical chest and it starts talking to you. It offers you 5 books to read so you don't become too bored before other people rescue you. Any 5 books you want, that can be purchased at book stores today. Please list the 5 books you would ask the magical talking treasure chest to give you. It is 100% that you will be rescued in the future and you have all that you need to survive until then(toilet paper, food, first aid stuff, shelter, friendly monkeys).

Talking treasure chest eh? I'd be more worried about being delirious and possible psychosis than any books it has to offer. I'd throw it into the sea. Thing is probably cursed!

How about (YMMV):

The Blackwell Companion to Philosophy
If Not, Winter: Fragments of Sappho
Maybe a collection of Byron
...or a collection of Tennyson
The Myth of Sisyphus, and Other Essays by Camus, because trapped on an island you might have...dark thoughts...

forgot to pack a survival book...
Gödel, Escher, Bach is worth consideration, but I'd hate to be trapped with it for years...
A book on pop physics would be nice, but i haven't found a deserted island physics book yet...
A dog-eared copy of Infinite Jest would look good to your rescuers

Hm... If this is to benefit you, you should give us an idea of what kind of books you like. I'm mainly a horror/fantasy guy myself, so I would require The Complete Works of H.P. Lovecraft (Cthulhu and other horror), Desperation by Stephen King (horror), The Way of Shadows by Brent Weeks (magic-wielding assassins), Twilight Falling by Paul S. Kemp (Forgotten Realms fantasy), and Wildwood Road by Christopher Golden (Ghost-like horror).

The Tartar Steppe
The Picture of Dorian Gray
The Narrative of Arthur Gordon Pym of Nantucket
Nineteen Eighty-Four
Neuromancer

Hmmmm, this is a tough one...

1. The Foundation Trilogy(Its all in one book) by Isaac Asimov

2. Silmarillion By J.R.R. Tolkien

3. Starship Troopers by Robert A. Heinlein

4. 1984 by George Orwell

5. Leviathan Wakes by James S.A. Corey

Ah, I forgot about Neuromancer, and it's on my computer! Shame on me.

Excuse my curiosioty, but how does answering this question help you?

If I was stuck in a deserted island with a magical chest for all company, I think I would be too depressed to read.

A survival guide, a book about raft building, an atlas of the area where I'm stranded (including sea currents), a medical map of the human body (with a chapter on first aid), and one of those do-it-yourself books with an included assembly set for a battery-powered radio.

Hmm. I think i'd go for my long-standing favorites. They're my comfort food: no matter how many times you read them, you never get tired of 'em!

1) The Lord of the Rings by J.R.R. Tolkien
2)The Egyptian by Mika Waltari
3-5) The Farseer trilogy by Robin Hobb

1) A book on survival in wilderness..

and then for fun:
2) Dune series by Frank Herbert (fits a desert island perfectly.. or was it a deserted island? ;)
3) Discovery of Heaven by Harry Mulisch
4) 100 years of solitude by Gabriel Garcia Marquez
5) The malazan series by Steven Eriksson

Wouldn't that count as three books?

K. Vonnegut, Breakfast of Champions (excellent read),
S. King, Misery (something to relate to in my situation),
Chuck Palahniuk, Fight Club (love the movie, never had a chance to read the book),
Ahmed Salman Rushdi, The Satanic Verses (tried to read it several times and every time something distracks me; isolation on the island would hopefuly help me to get to the end)
John Verdon, Think of a number (I'm reading it right now and I wouldn't like to have a long break)

No. The Lord of the Rings is not, despite popular belief, a trilogy. It's a single volume cut in three pieces by the publisher because paper was expensive during wartime.

1) The Gormenghast trilogy, Mervyn Peake (you can get it all in one book, and Mervyn Peake possibly the best writer of all time, except for... )
2) Burma Days - George Orwell (the best writer of all time)
3) Lonesome Dove, Larry McMurty (Long - contains characters in more depressing situations than you)
4) The Beach - Alex Garland (Terriffic lesson, exceptionally ironic)
5) For the term of his natural life - Marcus Clarke (Because it could always be worse)

Happy trip!