This is where you can change servers. Starred servers allow you to use P2P application like torrents.
This feature will allow you to choose OpenVPN/Routerpro mode whether UDP or TCP
By default, it is set to Openvpn UDP. For reliability, you can choose Reliable (TCP) mode. If you are located in Country with high censorship like China and you have Routerpro in your account then you can choose Routerpro connection mode.
This is much secured than Openvpn because it uses dual layer of encryption. This is designed for countries with high censorship.
BLOWFISH 128-BIT => Blowfish is fast but some see it as a weaker encryption.
STRONG (AES 128-BIT)=> This runs faster and is secured than Blowfish. It is widely and commonly used.
MILITARY (AES 256-BIT)=> This is the most secured and used for Top Secret Communication by the US government.
This can speed up VPN access on some smart mobile devices like iOS and Android. It will not affect computer but actually slows down PC access and may not work properly.