Go to http://www.picotech.com/software.html
and select the "PicoScope 2204" at Step 1 and then the "Software Development Kit" at Step 2 and you will have the sdk for the device. Included in this is a ps2000_fast_stream.vi and a PS2000_Block.llb
These will show you how to communicate, retrieve data, and display a waveform in LabView.
However you will need to write code for FFT yourself or find some suitable code on the web.