Does the hosting provider have both Linux and Windows options? Does it allow you to allocate space as you wish? Basically, is the hosting provider truly providing a dedicated server? In some cases, hosting providers sell “private servers” that still share space with other cohabitants. You want a dedicated server that is completely your own to customize and control.
Availability, price and employee familiarity often determines which operating systems are offered on dedicated servers. Variations of Linux and Unix (open source operating systems) are often included at no charge to the customer. Commercial operating systems include Microsoft Windows Server, provided through a special program called Microsoft SPLA. Red Hat Enterprise is a commercial version of Linux offered to hosting providers on a monthly fee basis. The monthly fee provides OS updates through the Red Hat Network using an application called Yum. Other operating systems are available from the open source community at no charge. These include CentOS, Fedora Core, Debian, and many other Linux distributions or BSD systems FreeBSD, NetBSD, OpenBSD.