Check out this great article by Scott Mitchell regarding data structures in .NET 2.0. It’s a six-part series that pretty much covers all that you’ll need to know.
It goes like this:
Part 1: An Introduction to Data Structures
Part 2: The Queue, Stack, and Hashtable
Part 3: Binary Trees and BSTs
Part 4: Building a Better Binary Search Tree
Part 5: From Trees to Graphs
Part 6: Efficiently Representing Sets