APDL or Workbench?
To choose through him, you must to know your level in usage of ANSYS. If you are beginner, than is better to start with ANSYS Classic (APDL or latest MAPDL). I have an good reason to tell you this: from my experience I observe that APDL is very ¨unfriendly¨ for beginners, because is not so intuitive like WB and all setups must be made by the hand. This is very useful because you will begin to understand how it works every command, which means every setup, where is useful or not. Other reason is that forcing you to made some hand calculus to check if your results corresponding to simulation. Because some simulations implicate more than two pieces in contact, using APDL you will be forced to learn about how it works , how can be changed, modified, etc. Using APDL you will learn to use nodes and elements for processing, solve and post-processing. Unfortunately, ANSYS start hard work with WB in this direction only from version 12.0. All older versions impose supplementary knowledge of APDL programing which are not easily. WB offers more intuitive interface, but unfortunately, from my point of view, without APADL experience is very difficult to have an good control on results and solution.
So, you must decide what is the direction in which you want to start, and the scope in which you want to use it.
Keep in touch.
My experience with APDL Vs. WB is the amount of control one has over the simulation in APDL is significantly higher then WB. For example I am working on a problem that requires a Tertiary creep equation (which is not built into ANSYS) for the material proprieties and so far APDL is the only one that can do the user defined non-linear tables, or equations for the material definitions within the simulation. However this is a very specialized project and for general problems WB I think would work great because of its easy of use. WB has the 13 creep equations that are built into APDL but not the options (that I can find anyway) to input properties that are not built into WB or APDL. So basically WB has most of what APDL has but lacks the more specialized stuff. Other notes on APDL is that you can create a "batch code" in a text file and run it in APDL and then if the code has problems or you want to change a specific part (like the force or the materiel) you can change the code in the text file and run it again very quickly. This cuts down on troubleshooting time immensely !! Final note (because I could talk about this all day) is that APDL and WB will more often then not, give you a solution and it is ultimately up to the user to determine if it is correct or if it is the desired out put and this is easier to accomplish if the user has a very good understanding of what goes into the code. In my opinion using the APDL part of ANSYS helps with that understanding. Thanks for reading and if you have any questions or comments, please do not be shy.
Hope this helps