I am going to get a VPS/VDS and will be hosting several websites, Some type of chat server (XMPP, Openfire or eJabberd), and possibly a Teamspeak server.
I want the server to be as efficient as possible. The server will have 1GB or RAM and one processor core until absolutely need to expand.
I have looked at Ubuntu, CentOS, and Linux Mint. I've been leaning toward Ubuntu but I have heard that there are problems with it, and that it isn't very efficient.