Recommend OS: Ubuntu 14.04(LTS) 64bit
Download address: http://releases.ubuntu.com/14.04/
Installation steps:
1) Start to install:

2) Choose installation type:

You should choose your installation type base-on your server or machine. You could choose “Something else” if you want to customize the partitions.
3) Disk partition:

If you choose “Something else” on above step, you should customize the partitions by yourself.
4) Choose timezone:

5) Choose keyboard type:

6) Fill in information:

7) Installing…:

8) Installation complete:

When the installation is complete, please reboot your machine.