[CentOS] trouble installing centos 6.8

Dear all,

I'm having trouble installing Centos 6.8, in a VM using VirtualBox, and hoping that someone on this distribution can help.

I'm running VirtualBox Version 5.1.4 r110228 (Qt5.5.1).

I downloaded .iso files for Centos 6.8: - CentOS-6.8-x86_64-bin-DVD1.iso - CentOS-6.8-x86_64-bin-DVD2.iso

I proceeded to set up a new VM, selecting Linux / RedHat 64 bit. I selected the DVD1 iso file above as "IDE Primary Master" and the DVD2 as "IDE Secondary Master".

I then clicked "Start", expecting to be able to install the operating system. Instead of gives me a bunch of output I don't understand, and then it just hangs. I've attached a screen-shot.

I tried to re-download the iso files, from a different mirror. Same issue.

Any ideas? Thank you Emma