Dear Thomas W.
Thank you for choosing National Instruments!
The DAQ Assistant may take some time depending on how much of hardware you have installed in your computer and on the specifications of your computer. If you have a slower computer, you will need to wait awhile as well. If it still does not load, you may need to uninstall and reinstall NI-DAQ 7.x. Also, if you are doing so, I recommend that you upgrade to the latest version of NI-DAQ which is 7.3.
For a tutorial on DAQ Assistant, go
here. Hope this information helps you in your endeavor.
Thanks and Regards
ShekharS
National Instruments