The official EQ2 site now has some class guides available that give some good information about the classes and their party roles. They haven't finished, but here's a link:
Crusader "The crusader is well suited for the role of the main tank. Medium armor and a good selection of defensive abilities combine for impressive results. They may be somewhat limited as a secondary tank due to their inability to deal significant damage, but can still put their defensive abilities to good use in this role. More than one crusader in the role of a secondary tank might stray into the realm of diminishing returns."
But it sounds like maybe you should go with
brawler (monk/bruiser):
"A brawler makes a decent main tank, but suffers somewhat from his poor damage mitigation ability. A brawler makes a very good secondary tank, however, using combat arts like Defend to improve the tanking ability of the main tank, and at the same time delivering excellent damage."
This should also clear up some of the arguments as to whether all fighters are created equal re: tanking.
Edit: fix typos add link
Edited, Fri Nov 19 20:37:59 2004 by Huxli