I would recommend the XTi as well. Your lenses will work on it, which puts you way ahead of the game already. Plus the D40x does not have a focus motor, meaning many Nikon lenses are manual focus only on it.

Also, be careful who you buy from. That price seems too low, as I just bought an XTi online for ~$515. If it seems too good to be true, it usually is - that website does not have a good reputation.
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