I'd vote for Nixon, hands down. I used to consider Reagan to be a good president and I still believe the optimism he projected was much needed at the time he was elected. But after doing some recent research, I've concluded that his administration was probably the most corrupt to serve this country in the modern era.
Nixon certainly was no saint and Watergate put a stain on the office that has never been fully removed. However, it seems that the Reagan administration had a wider breadth of corruption and the policies the Reagan administration pursued were generally far worse than that of the Nixon administration.
What did Nixon do so great to counterbalance his many crimes?
The Nixon administration had a lot more foresight into domestic issues like energy, health care, and the environment than the Reagan administration.