I don’t personally think Fury is that great at lower levels, if you don’t have +hit (and are going dual wield), but Arms with a two-hander is.
Shields aren’t really as good as you might think, and I wouldn’t assume that a healer would (or should) have a better idea of how you should play your class than you.
If you don’t know what your stances do, read the tooltips, and understand that. If you don’t know what your shield does, read the tooltip, and understand that.
There’s a pretty good guide from early Classic on Tanking, specifically for instance tanking (there’s also a lot of good discussion in the comments):