I remembered that in my early college days in "System Analysis and Design" one of the attributes that makes a good software/os/anything of a system is the principle of least suprise.
Well in one fine day(that is yesterday) the default theme in gnome
(bluecurve) just disappeared(really suprising that ).I tried to change that with gnome-theme-manager and the message popped up -no metacity or gconf not properly configured.
Metacity-what a name-anyway i read the doc pages in /usr/share/doc/metacity-blah/ and got nowhere.
As for gconf-I used to include 'gconf-config --cflags' in makefiles- now what else could have happened here.I checked everything in my power including the stupid gconf-editor(looks like windows registry-one of the million and one reason i hate windows) but i got nowhere.Maybe I missed something.
I tried man gnome-session and man default.session too, and i thought that if i delete everything related to gnome in $HOME (like
.gconf .gnome .gtkrc etc) everything will be ok(still nothing).I reached /etc/gconf and if i know anything it looks allright .I also tried to use /usr/share/themes/bluecurve/gtk/gtkrc but it did not worked.
I also copied /usr/share/gnome/../default.session into $HOME.
Still not working -it looks ugly and really bad.
Now this is beyond me so i thought i should come here.
Incidentally if you have not got it yet my distro is rh9.0

Try creating another user and see if that user has access to bluecurve. if you do have bluecurve then it is only corrupted on a per user basis. Try to copy the new $HOME directory to your current user $HOME directory. Or delete the old user (backing up anything of import of course). And just become the new user.

If not then you are truly missing metacity and possibly some other files. You'll need all the rpms you are missing and uninstall/reinstall or just try to install metacity etc. If that fails rpm the whole package for gnome. I would suggest using apt for a job like this. If you have/know apt then use it, if you don't search google/linux for apt4rpm and you will soon see what I mean. If you would rather not go thru the hassle of learning apt right now post back and I'll walk you thru it.

ok i had already tried the other user bit.
now i think the only solution right now is reinstalling -nobody came up with a good way
by the way metacity is installed
why do you think /usr/share/doc/metacity-blah/exists
anyway i could have found out with
rpm -q metacity
i tried its varient rpm -qil metacity too.
and finally - i use debian too(Got a hint!)