OK, that's great. Thanks for your help so far 
I downloaded the latest current.gallery2.zip and installed that.
But, after going through all the setup (which failed to install comments and members for some reason, but I thought maybe that wasn't crucial) I now get:
Fatal error: requireonce(): Failed opening required '/pub/home/woozle91/htdocs/gallery2/modules/core/classes/../../../themes//theme.inc' (include_path='.:/usr/local/share/pear') in /pub/home/woozle91/htdocs/gallery2/modules/core/classes/GalleryCoreApi.class on line 2318
when I try to go into g2.
The "themes" bit looks a bit funny to me...?
Rob