I would suggest that the differences in submarine warfare has advanced a quantum leap or two in the last 50 years. I have to disagree with your opinion on submariners in WWII and today experiencing the same thing in battle. The ONLY thing that would be the same is the terror of being at war with someone wanting to kill you as you are trying to kill them. There is no destroyers racing over head nor is there going to be any depth charges dropping overhead today.
Modern submarines are true sharks of the deep. Be they diesel or nucs, a boat's CO will not transmit on an active sonar if he has any sense at all. Today's modern passive acoustic sonars have increadibly syphisticated signal processing that permit accurate fire control solutions to be generated while mainitaining your anonimity and never having to see your target. Add this to a competent group of sonar ratings who can classify the contact and you have a lethal combination. Now add the fire power. Once you have an acceptable set of parameters on your foe you would fire a torpedo dived and not on the surface or at periscope depth. Being on the surface is suicidal and being at PD invokes the possibility of detection by radar (and there are some awsome radars out there today). With a modern torpedo you can fire it at ranges in excess of 20,000 yards...and never see the target let alone the whites of their eyes! Oh ya, you'll still hear the boom at that rang too. Thus picking up survivors is really not an option today.
At depth you can take advantage of different water layers (bathimetric profile) to hide more effectively. Depending where you are in the world this may work very well for you or not at all. The time of the day and season of the year also impacts upon water layers as well as how close you are to land, river mouths etc. Acoustic signals bend all over the place in the water and you need to know exactly how they respond to take maximum advantage of this feature.
As for transmitting on a radio to communicate, that can get you detected however once again technology has made some major break thru's here too. With Satcom (satellite communications) the signal power is very low and the frequency very high. This aids in limiting detection opportunities for your foe. Radios with frequency hopping capability also make it difficult to detect the path of the transmitting signal. Submarines can also use slot buoys which are preprogrammed radio beacons that can transmit after the boat has left the area. But all-in-all a proper submarine fleet will not transmit but merely receive message traffic and carry on.
I hope these tidbits help define the hugh delta between submarines now and 50 years ago.

Cheers.