Well, the simple answer is to leave 3.7 alone, wait for the new server and then migrate the existing data.
If you think about it, there is no difference migrating to V4 on your current "server" and then moving it to the new server than waiting.
If you migrate the data now, then you will have to move the databases and install SQL Server again on the server. It's not that you can't move them, you can. But, it just makes sense to do it once. Sure SQL can talk to SQL.
Also, I guess "main computer" on a P2P is better than pseudoserver.
