How to choose cables for my system

He doesn't want to play with cables at the moment. He is new to the US and has more important things to do. The man just wants good relatavely inexpensive cables to start playing music. To set it and forget it for at least couple of years.
In any case, new and often used cables too need break-in time to sound best. Don't judge the cable's performance based on how it sounds first 50-100 hours though good cable will not sound like junk even the first minute of play. Some cable manufacturers, like Purist Audio, say 200 hours is needed for a cable to open up completely. I am sure it varies from brand to brand and perhaps even from model to model.

Generic 12 gauge speaker wire for about $.40 a foot will be indistinguishable from anything at the same gauge unless you know what you're listening to and the placebo effect can work its magic.

Generic interconnects work the same way. I spend at little more for $1.55 total per 3' interconnect as insurance against galvanic corrosion with gold plated RCA jacks.

Or concede that it's guy jewelry, costs less than anything with a motor, and buy whatever looks nicest.

If you want better sound invest some time in speaker + listener placement (which may not meet spousal approval), acoustic treatments, or more accurate speakers.

Many thanks all for your quick feed back. My system is back to life and so am I, spent the whole MLK's week end home revisiting my beloved music. Couldn't have been better to celebrate such a landmark anniversary.
Wishing you all the very best
Massimo