Which Arduino board to use?

hi,

I am doing my project on curtain automation system using an arduino. i will be using a motor shield to control the speed of the motor and i am also planing to use a Ethernet shield to control the curtain using a mobile phone application.

i am confused on which arduino board i need to use in this case :(

Is it possible to fit both the shields on a arduino uno board? or should i have to buy a mega? or should i have separate arduino boards for each shields and then connect them together..

please help me with this.. your opinions are truly appreciated.. thanks