I read this several years ago so the details are sketchy..I really liked it though and would like to find more by the same author. I think it was published in the 90s. I think the hardcover version had a mostly shiny gray cover.

There's a group of people living on a very cold planet. I remember the main male character caught animals to eat with traps. His wife is also a character. I think they've been cut off from the rest of human civilization.

There's a spaceship on the planet, or they build one, and many (but not all) of the people of this planet leave. I think I remember this being a fairly desperate move on their part.

It's a long trip, even traveling at relativistic speeds. There's some sort of farming done on the ship, I think. An ark ship, if you will. However, things start to go wrong. One thing that happens is one room keeps despressurizing, and no matter how many times it is inspected, nothing can be found wrong with it.

Eventually, they land on a planet. I think there's only four or so characters alive by this point? Two of them are the aforementioned guy and his wife. I remember only a few on the planet. They're in some sort of ghost town and a mysterious man appears and kills one of them in a very over-the-top fantastical way. The man delivers some sort of bizzaro dues-ex-machina to the story, explaining the problems with the ship.

Any help would be appreciated! :)

Hmm.  Well, this isn't going to be your answer, but there is a 5-book series by Orson Scott Card that follows a story arc something like that.  The first book of the series is The Memory of Earth.  Since you liked the unknown book, maybe you would like this.

Hmmm at first I thought it might be something I've read, but after checking I guess not.  If no one here can help I can tell you where else to ask - if you have Usenet, or Google Groups, go to rec.arts.sf.written and ask there. Someone will know it.

Cyndi

 Doesn't sound familiar to me, but check over at www.abebooks.com   They have a section called Booksleuth and someone over there may be able to help.  They are great at finding long lost titles with little info.

I guess this is a bit old by now...but could you be thinking of Forever Free by Joe Haldeman?  It is the sequel to the Forever War, written much, much later.  I don't remember if the ship was an ark, but the group travels from a colony world back to Earth after communication is cut off, and the ending is similar to what you describe.

OMG! That's it! I asked this about this book in maybe 6 places and no one had any idea.

I had thought Camoflague was my first Joe Haldeman book too..and then I read Forever War with no idea that it came before this one! At some point I must have read a description of this book after reading it and decided not to read it even though I remember liking it..

Glad I could help...Joe Haldeman is one of my favorite authors and I've read all of his books, including a couple of bad Star Trek novels from the '70s.  My favorites are probably Buying Time and Tool of the Trade. 

You might also enjoy "The Black Sun" by Jack Williamson.  It was publsihed in 1997 and was one of his last books.  Very similar in that a small group leave Earth on a long journey and end up on a dying planet in a dying solar system, where they have to try anything to survive.