Go ahead and file a complaint, but the FCC has no magical way to stop scammers who may be operating outside the country, routing their calls via the internet and possibly spoofing their caller ID.
"We need the Do Not Call Registry reformed so the district attorney can start prosecuting these parasite solicitors."
Your local or state District Attorney can't prosecute federal crimes.
The DNC registry works great - but only with legitimate telemarketers. It has no magic power to stop scammers who don't follow the rules, route their calls over the internet, are based in foreign countries, and use caller ID spoofing.
If a caller is legitimate, they'll leave a number and a message and they won't keep calling.
If the caller is a scammer, then the number may be spoofed, so if you do reach someone, it may be an innocent party or it might be a non-working number.
If the caller is a scammer and you do get a real phone number, then all you are doing is confirming that they reached a valid number - and they'll sell your number to other scammers.