can spent nuclear fuel rods be re used to provide for small scale power generation and desalination plants?

Answer 1

Yes, they can. The power required for evaporating off the water might be a concern, and direct, or indirect heating would be an issue if using the spent fuel directly. Generally, the fuel would be used as a heat source for providing thermocouple devices with the heat they need to make electricity.
There are very efficient, low volume ways to use the sun to evaporate water to get the salt out of it that use simple plastic cover sheets.