moving from 1 Ad to another

Hi,

I have 2 DCs, 10.0.0.x-primary- where all 5 roles are on this and an additional DC 10.0.0.y. both have dns servers running as well. Both runs Win Server 2008 Standard 32bit.

I would like to create a new AD, with Win Server 2012 R2 Standard 64bit and i would like to make this one primary-that is, move all roles to this one. and also i would like to decommission the 10.0.0.y 

the first step that i would like to do is to remove the all roles from the additional DC-that is remove domain controller, remove dns

then i would create my new server-10.0.0.z

I would like to know the best way to remove the additional DC and then install 10.0.0.z, and moves the roles from 10.0.0.x to that one.

i would like to know if there is any config that needs to be done regarding the DC as the new one will have win2012 64bit.

any help pls.

thanks.