I've tried reading Heart of Darkness twice and listening to it on tape once and I just couldn't get into it. I never even got as far as Africa in the story. I can't say why other than there was too much story setup for me.

I would start with "Lord Jim" but switch immediately to "Nostromo" if you are not soon immersed and entranced. Both are amazing novels. "Typhoon" is a very different kind of book, a real adventure novel (not normally appealing to me) with quite a bit of humor as well as the more familar testing-a-man's-mettle theme. The central storm is described with a cinematic vividness that actually made me a little bit seasick. That doesn't sound like a pleasant experience, but it was great. I read "The Secret Sharer" only recently and found it intriguing but never resonant on the same level as the others I've mentioned.