[CentOS] VPN suggestions centos 6, 7

Folks

I would like to have my windows 7 laptop communicate with my home 
server via a VPN, in such a way that it appears to be "inside" my 
home network.  It should not only let me appear to be at home for any 
external query, but also let me access my computers inside my home.

I already have this working using M$'s PPTP using my home Centos 6 
gateway/router as the PoPToP server.  However, I am concerned about 
the privacy/security of such a connection.

I have seen discussions of OpenVPN, OpenSwan, LibreVPN, StrongSwan 
(and probably others I haven't noted).  I'd be interested in hearing 
from anyone who wishes to comment about which to use, with the 
following requirements:

1)  As noted, it should be secure (anti NSA?)
2)  Works on Centos 6 and Centos 7 and Windows 7 (and for the future, 
Windows 10)
3)  Can be set up on the server with command line interfaces only (no GUI)

And, should not be a nightmare to set up.

Any thoughts?

David