The channel lists adapts to the type of DAQmx Create Channel that you use. Do you see the text below the DAQmx Create Channel? If your channel is displaying only analog input channels, then the DAQmx Create Channel type is AI Voltage. If you want to use digital input channels, change the type to Digital Input. Click on the little arrow on the right side. This is called a polymorphic VI selector. You can do the same thing by right clicking on the VI and do a Select Type.
Mark has a good point. If you change the type of DAQmx Create Channel and you already have a physical channel wired, you will have to go to I/O Name Filtering to change the channel types displayed. If you change the DAQmx Create Channel and then create a channel control by selecting Create Control, you'll get the correct type automatically.