It's nice to see someone tackling some serious literature. For Dostoyevsky, I'd recommend "Notes from the Underground" to start with then "Crime and Punishment" next. Brothers Karamazov is good, but those other two are my favorites (Notes from the Underground is a novelette, so a much easier intro to his writing). As for Joyce, I'd recommend reading Portrait of the Artist as a Young Man first--makes Ulysses so much easier, but still hard. I'd pass on Finnegan's Wake.

If you want a light book, try Catch 22 by Joseph Heller, Huck Finn by Twain, or Animal Farm by George Orwell.
Other classics I like of the top of my head:
Heart of Darkness by Joseph Conrad (inspiration for Apocalypse Now)
Anything by Franz Kafka (start with The Metamorphosis)
1984 by Orwell
The Sound and the Fury by Faulkner (very hard--almost Ulysses-like; might try Light in August first)
Invisible Man by Ralph Ellison
Pedro Paramo by Juan Rulfo (the original magical realist)
Anyway--all of these are great books. Let me know if you need any more suggestions.