Are you using Oracle VM Server for x86 or Oracle VM VirtualBox. It sounds to me like you are using VM VirtualBox, in which case the reason why you cannot mount the VirtualBox shared folder is probably because you did not install the VirtualBox Guest additions. How to do that is explained in details in the standard VirtualBox documentation.
If you installed Oracle Linux 6, it does not provide a GUI desktop by default. To get a GUI Desktop like Gnome, please search the forum. There are several previous posts about this topic to help you solve that issue, e.g. Re: Is there a GUI console for Oracle Linux
GUI mode is not required to install the Guest Additions. Chapter�4.�Guest Additions
The following should work under Oracle Linux:
1. Select "Install Guest additions" from the VM Devices menu to attach the built-in installation media
2. Mount the media and install the required software:
su - root yum -y install gcc kernel-uek-devel-$(uname -r) mount /dev/cdrom /mnt cd /mnt ./VBoxLinuxAdditions.run cd / umount /mnt
You should receive some info about missing kernel-headers, which you can ignore.