I think we've had metered pay-as-you-go telephony experiences for most of the last century. Just ask AT&T how their business has worked over the decades. It's kind-of pointless indicating to the USPTO that there is abundant ancient prior art, but I expect that if Microsoft ever try selling a licence to this patent, it will get invalidated within seconds.
It's not likely that the ISP would stay in business long if they did that. I imagine it would be considered criminal fraud if you kept taking someone's money and stopped providing the service you had contracted to provide.
Try http://opensuse.org/ . You can set this up so you can get a 'console' session from a web browser (using VNC and java, if you must know); there are more secure ways of doing it, but that will get you started. Backup tends to be application-specific; figure out how to take backups of your database, and how you will test your ability to restore from them.