How can I install alternate desktop environment

I have openSUSE 11.2 installed with KDE4 and is wondering what is the proper way to install another desktop/window manager.

Installing fluxbox is straight forward with ***zypper install fluxbox


what about gnome and lxde?

How will the default application be affected
e.g. when I login into KDE, video is defaulted to smplayer

If gnome/lxde is installed
will the default app change with the desktop environment or
will one app be defaulted to all desktop environment?

For Gnome use YaST > Software > Software Manager. Choose Patterns from the tabs above and look for the Gnome desktop ones. Select and install.

At Gui login (so do not use auto login) you can choose which DE you want to use for the moment.

And I suppose thet different desktops might have different ideas about which applications to use for which files types. Seems logical to me that Gnome will use another editor than KDE when you click a text file. And of course a lot of this is configurable.