Quote from: Bestcoin-fan on October 26, 2017, 08:05:53 PM

As for the speed, my home internet connection is very fast now but the blockchain downloading (syncing) was VERY slow. My download bandwidth was being used at 2-3% only.

Core downloads blocks from many sources and it is comparable to a torrent. The downloading itself is fast but the validation process is very slow. Its not a problem with the internet speed but rather, your hardware speed.

Quote from: Bestcoin-fan on October 26, 2017, 08:05:53 PM

But if there is a security risk, then maybe is there a Bitcoin Core command or something to validate all its database against the actual real blockchain?

There really isn't a security risk. The security risk it has would be the same as a user downloading any other files from the internet. If you want to be extra safe, use -reindex when you start Bitcoin Core up. Be warned that it could take days for it to be completed.

Quote from: miguelmorales85 on October 25, 2017, 08:38:17 PM

the chain that will be chosen as the dominatn one is that with the most nodes running up. So if you support Bitcoin Core you must run a Bitcoin Core node and accept and check transactions with it.

good luck

No. Nothing is chosen in the hardfork. Both chain will still exist.

Quote from: miguelmorales85 on October 26, 2017, 08:09:35 PM

If you want to help other to download the whole blockchain just make sure your node accepts incoming connections.

No. Outgoing connections also helps others to synchronize their blockchain.