Dragonlance...
I'd recomend starting with the "main" storylines THEN branching out. Which means read the Chronicles Trilogy (
Dragons of the Autum Twilight, ...Winter Nights, ...Spring Dawning), then teh Legend's Trilogy (
Time of..., War of..., Test of the Twins), then The Second Generation and Dragons of the Summer Flame, then the War of the Souls Trilogy (And I forget all the titles but they also start with "Dragons of...") Then any of the other books in whatever order you feel like.
Though not many people I've talked to will suggest reading teh Preludes and stuff unless you are a rabbid fan or something since they are sub-par to the characters in the original books.
Dragonriders of Pern...
Anne McCaffery recomends you read them in "Published" order, some will say in story Chronological order... and others will tell you it don't matter.
Personaly I fall in that last group, so long as its not in teh middle of the ONE trillogy of the series.
Anne's Site (
http://www.annemccaffrey.net/ ) I believe has a listing of BOTH Published and in story chronological orders of teh books.
Wheel of time...
Book one then two then three... they usually have what book number they are in teh series on the front cover if you look.