what os for file server

[cisto1999]

at first i have to say that i am totally new on this topic... But i hope i can describe clearly what i want to do: i want to build my own file server/nas. About 10 different people should have access to the files and should be able to back up and synchronize their files. The server will be connected in a homenetwork of which firewall i won't have access to... So the file transfer and synchronization has to work on the standard ports because all the users have their pc outside this homenetwork. Best solution would be if everybody who has access to this server could create his own virtual partition on his pc or mac where he can save all the data he wants to be saved on the nas/file server.

My question: which software can you recommend for this? Would it be the best if i install linux and then seafile? Which things i have to consider that the file server /nas is accessable from outside the homenetwork?

Thanks in advance for all your help

[Shd0w2]

Double post, I'm going to actually post on newest one, hopefully everyone else will too.