If you all haven't gone out and seen Citizen Kane yet, I would highly, highly recommend it. It is one of the most technically accomplished films ever made.
The camerawork itself is my favorite aspect of this film. The scenes I would highlight:
1. The initial opening scene with the closeup on Kane's lips saying "Rosebud," and the rolling snow globe.
2. The shot through the window of the young Kane in the snow.
3. The use of vertical lines during the party scene at the newspaper.
4. The montage with Kane and his wife and the newspapers.
5. The scene with Kane's wife completing a puzzle.
I would recommend, as a companion, the documentary Visions of Light, which is a fascinating look at the history of cinematography, and does a great analysis of Kane.
I would also recommend if you get the Kane DVD, that you watch the documentary Battle Over Citizen Kane, which provides an excellent, excellent background on the film's controversy and the campaign to prevent it from having any critical and commerical success in its time.