Our TFS2012 deployment is currently quite simple: Virtual Windows Server with TFS, Sharepoint, Reporting, SQL Server and Builds all on the same machine!
Is using the TFS admin console backup tool and/or backup of the entire machine enough to recover from a disaster?
There is no clear-cut criteria, you may take a look at TFS planning and disaster recovery guidance for a more comprehensive answer. Shortly, you must be sure at least that
This guarantees that you are able to recover, but it can take a long time, depending on the disaster impact (someone deleted a record vs. the server room has burnt) and the size of your data.