Upgrade Options

I have an all purpose server (mail, web, samba, etc.) running at my house. Its currently running 6.2 (its a shuttle KPC). I'd like to upgrade to 7.1 but I want to minimize downtime. So I see that I have 2 options:

1. Upgrade freeBSD from 6.2 to 7.1. I have no experience doing this but I'm sure I can dig up some instructions.

2. Build a new box using vmware and then dump it to a drive. Install this in the KPC. If I use the GENERIC kernel is this going to cause a problem? Anyone have any experience doing this?

I'm thinking about option 2 for purposes of minimizing downtime. Anyone have any experience doing this? Option 1 will require me to recompile all my ports anyway...