CentOS and Ubuntu servers hosted

A client has an environment consisting of a mixture of CentOS and Ubuntu servers hosted at Amazon. The environment has reached a size where it makes sense to implement a configuration management system. The client has asked you to provide a recommendation of system to use. Their requirements are:

● The solution must be open source
● It must be easy to deploy machines and have them operational as soon as possible
● It must be possible to add machines to the system with minimal manual effort
● The system must be able to scale with the environment
● There must be a web-based front end to manage the system
● The system must provide reports of compliance and changes to the environment
● Managed systems must be added to a monitoring system (Nagios) automatically

Please do the following:

1 Can you identify at least two solutions to be considered?
2 What are the strengths and weaknesses of the two best solutions?
3 What solution do you recommend? Discuss why it was the one ultimately chosen.

i guess cent os is the best for hosting service.
there is similar article regarding window and linux hosting in the link
www.tukihost.com