Welcome and don't worry, we all have to start somewhere.
First thing for you to know is that pre/pro stands for Preamp/Processor. The "preamp" pertains to audio and the "processor" pertains to audio & video processing. Your Denon AVR2112 is a pre/pro coupled with a multi channel power amp all in one box.
Second, to build your 5.1 system, you need to add a center channel and then a sub as you outline above. You will now have a 3.1 system. Finally you can consider surrounds to make it a 5.1 or 7.1 system.
Last, and hate to break it you, is your question about about adding amps for your main speakers. You can't do it with your current Denon AVR. It has no L/R pre-outs (stands for Preamp/Outputs). You are stuck using your Denons internal amps. The only way to get more and higher power into your B&W's is to ditch the Denon 2112 and get an AVR with a full set of pre-outs or go the separates route - a pre/pro and power amp in two separate cases. Hope this helps and good luck.
First thing for you to know is that pre/pro stands for Preamp/Processor. The "preamp" pertains to audio and the "processor" pertains to audio & video processing. Your Denon AVR2112 is a pre/pro coupled with a multi channel power amp all in one box.
Second, to build your 5.1 system, you need to add a center channel and then a sub as you outline above. You will now have a 3.1 system. Finally you can consider surrounds to make it a 5.1 or 7.1 system.
Last, and hate to break it you, is your question about about adding amps for your main speakers. You can't do it with your current Denon AVR. It has no L/R pre-outs (stands for Preamp/Outputs). You are stuck using your Denons internal amps. The only way to get more and higher power into your B&W's is to ditch the Denon 2112 and get an AVR with a full set of pre-outs or go the separates route - a pre/pro and power amp in two separate cases. Hope this helps and good luck.