Spider provides three levels of difficulty: Easy (all Spades), Medium (Spades and Hearts), and Challenging (all four suits). Use the Variations button in the toolbar at the top of the Spider game window to set the desired difficulty.
The statistics for each variation are also tracked separately.
The Variations panel also includes options for the number of cards dealt and whether moving builds of cards is limited to those in same suit order (the default is same suit moves).