I m using Spectral Measurements Express VI to perform FFT analysis. There are options for configuring different types of windows like Hamming, Hanning, etc... But that's inside the configuration box. What if I want to make a provision for selecting different windows on the front panel....???
as I'm not experienced with express vis I can only suggest to convert your code to the non-express version and go from there. I think if you right-click the express vi there is an option to do the conversion. If so you may get a terminal to wire a control to for the window mode.