They are three types of VPN technology.
Which is the easiest to configure? PPTP > L2TP > openVPN.
Most operating systems and devices have built-in support for PPTP and you simply need to fill in a server address, a username and password to configure and no additional software is needed.
Which is least likely to be blocked? openVPN > L2TP > PPTP
Both PPTP & L2TP uses fixed ports, if your service provider or firewall blocks certain communication ports used by PPTP or L2TP, they won’t work. openVPN can be configured to use any port (on the server side) and supports multiple protocols. For example, openVPN can be configured to use TCP on 443 which is used also by secured websites like banks. If your service provider does not blocked secured websites (very unlikely), openVPN will work as your service provider won’t be able to tell the difference between openVPN connection or secured sites connection.
If PPTP doesn’t work. Try L2TP or openVPN.
Which is the most secure? openVPN > L2TP > PPTP
openVPN supports standard SSL encryption and it’s very secure.
Which is the fastest? more or less the same.
Some people say openVPN on UDP is the fastest but I think they are all more or less the same. Speed depends much more on your connection to the server and other factors.
It seems openVPN is the best?
openVPN is good, but it requires installing additional software. On some devices it can be complicated. Sometimes a user is required to deal with certificates, configuration files, etc. If PPTP works, you may choose not to bother with openVPN.