It really is as simple as a single install. You can move your database and repository files to the new server from the version 9.2 server. Then you can install 10.2 and register the 9.2 repository files/database. It will notice that the version needs to be updated and perform the updates. Same goes for Workflow, Forms etc. The most difficult part might be updating the workflow references to the old server name, I can't find anyway to globally change the workflow connection information, it must be done for each published workflow. The rest of the products can be updated through the associated configuration app. If you used localhost instead of machine name, your safe.
I have not found a way to pre-install yet, because you can't even start the install until you deactivate the old server. The install time is not very time consuming though, takes maybe 30 minutes to install the entire suite. Most of the time spent is in configuring which you can't do until the data is moved anyways. You can deactivate the old server using the command line utility instead of an uninstall, which is a nice fast and recoverable way to do it.