For EKG's, FA should be fine. Definitely know the appearance of A-Fib, V-Fib, NSR (and what the wave forms mean), and maybe 1st degree AV block (FA has pics of these and a couple more, it's plenty). Most q's don't require you to even recognize, just more to know about them (why A-fib is bad, why V-fib is bad) and contexts for each.
Murmurs- FA again has good diagrams for everything. With Fredv2, you may have to recognize them (I didn't take on v2, but had one audio q and had classmates who had more). What I would suggest knowing is the description of them (fixed/split s2 with ASD, crescendo-decrescendo for AS, PDA machinery, etc.). For my audio q, and for my classmates', you have a REALLY strong idea based on the passage, and the audio simply confirms (or sounds like static, in which case, you still stick with your original idea). Hope this helps. : D.