I've been using Linux+Plesk Virtual Server as a web server for a while, but I want to give a try on doing it manually, so my question is:

I'll have a server which is: 80GB HDD, 4GB RAM, 1TB Bandwith, 1 Dedicated IP. And I use the following things on my Virtual nowadays:

• Mail server
• DNS server
• Apache + PHP 5.5 + MySQL
• FTP
• SSH

My question is, without Plesk, can I achieve manually all those functionalities -know that I am not a terminal pro-, actually upgrading some of them to look like that with ubuntu server?:

• Mail server (with a nice webmail included)
• DNS server
• nginx + PHP 5.5 + MySQL + MongoDB
• FTP + SFTP
• SSH
• GIT Server

Which ubuntu server should I chose?

[EDIT]

I almost forgot, I'd like to know how much Bandwith and CPU is using each of my webapps (one per domain usually), and the overall (not just from the webapps, but also mail, dns, etc...) ... usually Plesk does that for me, and I don't know how to measure that without it!