I can assure you that the Arduino would work for this, but as to if the best, I wouldn't know. Arduino was my first and only microcontroller, so I can't compare to others such as mbed, etc.
The arduino you need depends on how many I/Os you need. If you can deal with only about 21, then you could use the Duemilanove, but if you need a lot more, you might want to consider the Mega.