Gotta agree, Jordan's Wheel of Time series in terrific. One of the things I like is that (you men may not realize how rare this is in fantasy books) the female characters all have actual personalities of their own. (Though Jordan does certainly seem to have bondage and torture fantasies....)

I lean more toward humor--here are some of my favorite humor series:

1. Terry Pratchett's Discworld series--a wonderfully silly fantasy series, which improves and adds a wonderful cast of characters as it goes on. The Grim Reaper is a regular character, and somehow one of the most endearing.

2. Robert Asprin's Myth series and Phule's Company series. Myth Adventures feature the adventures of a wizard's apprentice, Skeeve, as he learns magic, works to become successful, and then is nearly destroyed by success. Funny and interesting, unfortunately Asprin got writer's block and left it unfinished. Tending toward navel-gazing toward the end. Phule's Company is the story of a rich executive who takes command of the worst unit of the space legion, and turns it around using his money and management skills.

3. Douglas Adams Hitchhiker series. The basis of all modern fantasy/science fiction humor. Monty Python In Space. Gotta read.

4. Pat McManus's books--outdoorsman's columns from a sporting magazine, with hilariously skewed adventures from his youth. (At least read the articles "Deer on a bicycle" and "The Two-Wheeled ATV.")

5. A Series of Unfortunate Events by Lemony Snicket--a so-called childrens series filled with dark humor, clever wordplay, and melodramatically parodic situations. If you think while you read, you will snicker through the entire series. "If you are allergic to a thing, then it is unwise to put that thing in your mouth, especially if the thing is cats."

6. Junie B Jones--another kids series (younger) about an irrepressible kindergartner. Hilarious, at any age.