Hi Anthony,
The answer to your first queston would be using the Cisco Feature Navigator here:
www.cisco.com/go/fn
Migration Process from IPv4 to IPv6 should be done using straight forward approach, before you migrate to a pure IPv6 Network , you need to make sure your hardware supports dual Stack IPv4 and IPv6, you will start with normall Ipv6 Tunneling technique Carrying IPv6 over native IPv4.
Then ,after you make sure you core Infrastructure or the ISP infrastructure supports Ipv6 Backbone natively on thier infrastructure, then you can fully migrate to IPv6.
However, As Paolo noted, even a Service Provider doesnt fully migrate to IPv6, but rather , they do plan to implemnt IPv6 in thier core infrastructure to support dual Stack IPv4 and IPv6 which makes them a V4 and V6 backbone carrier.
HTH
Mohamed
