#2 Apr 25, 2008 03:57
You have to upgrade the database when you upgrade the files, meaning it's both or neither. So what I would do if I was you is first move the files and database exactly as they are to the new home, then upgrade to at least 1.10.3 and ideally 2.4.1. Both are good stable releases, but your 1.9 skin won't work in 2.anything so you might want to stick with 1.10.3 for a while. OTOH sooner or later you're going to want/need to upgrade again and that will mean change the skin because there won't be anymore 1.whatever releases.
So I guess the thing to ask yourself is how much you absolutely need your skin to be exactly what it is. Oh and hacks too. Lots of stuff changed, so if you have a lot of hacks then say byebye to 'em.
There is a forum post and manual page about plugins from the 1.* generation that have and have not been upgraded to the 2.* world. The ones that haven't probably never will be as it seems the author(s) isn't/aren't keeping their products alive.