shafe88 :
What's the easiest way to turn my old Pentium D computer into a Linux server. Looking for something easy that's point an click and supports wifi. I would like to have acesses to it from windows and linux. The main use is download and uploading files to it to be accessed from my others computers.
Check out CentOS 6.5. It's a great server and workstation oriented distribution that's a clone of RedHat Enterprise Linux, which is hands down the most professional distribution available.
Alternatively, check out Ubuntu Server. It's a bit less mature than CentOS but has a decent community built around it.