OK, so I'm not a mechanic but here's the low down to the best of my knowledge and what I am doing with my own car:
1. Dual mass flywheel chattering at idle - replace it ASAP. Like I said, my car is 2009 59 plate DSG and I only changed the flywheel, I think everyone you are speaking to is assuming the car is a manual. Indeed, if it were manual then I would say the same - change everything while it is out.
2. Turbo whine - sometimes a whining/whistling turbo will go pop immediately, others have covered 20,000 miles plus whilst making that noise and have been fine. You need to isolate the cause of the noise. Is the turbo starved of oil? In which case look at the oil pump. Is there a boost leak which is causing the turbo to spin faster (and make noise) trying to achieve a boost pressure it won't ever hit because there is a leak. Check all the pipework to and from the air intake and the intercooler. Personally, I'd leave it on the car until it pops and my turbo is whistling right now on my car and I've left it on for now.
