Allison,
What you have should work without any problem, and without any programming, if you follow the instructions in the EDU-2004-RC Reference Guide on our Documentation web page:
http://innovationfirst.com/FIRSTRobo...umentation.htm
Basically you should connect the three servo outputs on the bottom right corner of your receiver to the connectors labeled "R/C PWM IN" on your Mini-RC. To see what functions these inputs control by default, refer to the Mini RC 2004 Default Software Guide, also on our Documentation page.
Changing the function is a relatively simple matter of programming, which even a non-programmer can easily learn to do by following the instructions in the 2004 Programming Reference Guide.
Further information on which radio systems to use can be found in the Radio Control Selection Guide on our White Papers web page:
http://innovationfirst.com/FIRSTRobo...ite_papers.htm
It does look like you are using a model designed for use with aircraft, and to modify it to operate on the ground vehicle frequencies (as you should legally be doing) would involve sending it to the manufacturer to retune it. Once modified for ground frequency use, you would then use crystals to select the channel. Changing from air to ground frequencies is not simply a matter of swapping crystals. Your local hobby shop should be able to answer any questions you have about R/C systems.
Regards,
Innovation First, Inc.