#2 Feb 05, 2008 02:32
Upgrading your installation will upgrade the database at the same time, but it will NOT automagically move you up to php 5.anything. So what you would do is upgrade first your php on your server, then upgrade your b2evolution package. Your 2.4.0 files will notice that the database is from 1.10.3 and not let you use your blog until you follow the upgrade procedure.
Skins are a different thing. VERY different. http://manual.b2evolution.net/Skins_2.0 should get you going along that path?