I've seen people try to explain this on here, and the answer is here but its usually found in a mass of multiple posts. So after installing KDE4 myself and wanting to uninstall it (not quite perfected to my liking yet), I'm going to share with you how I was able to do this.
Firstly the installation procedure:
1. Open up konsole and run sudo kate /etc/apt/sources.list
2. Add the line deb http://ppa.launchpad.net/kubuntu-members-kde4/ubuntu gutsy main at the very bottom and save the file.
3. From konsole run sudo apt-get update
4. Again from konsole run sudo apt-get install kde4-core
5. Select yes to the prompts, you'll most likely get a verification warning, just select yes to continue with that as well.
6. When it is complete, reboot the system and from the login manager select KDE4 as the session.
Hopefully you didn't run into any problems as I did not.
Now should you want to uninstall KDE4 after following the above procedure, then follow these steps:
1. Restart and at the login manager select KDE (not KDE4) as the session.
2. Open up konsole and run sudo apt-get remove kdelibs5 --purge (thats 2 dashes before purge)
3. When that has finished run sudo apt-get install kubuntu-desktop adept kdm
Once the uninstall is complete restart the system. At the login manager the menu should not have KDE4 showing anymore and if you login to KDE everything should be the way it was.
The only things I noticed are that my login manager wallpaper, settings and etc had reverted back to default. Those can easily be restored the way you want them through K-Menu > System Settings > Advanced > Login Manager
As well as the default applications had been reinstalled, so if you uninstalled any of the default programs, you'll need to open up K-Menu > Add/Remove Programs and remove them again.
Hope this is helpful.
Firstly the installation procedure:
1. Open up konsole and run sudo kate /etc/apt/sources.list
2. Add the line deb http://ppa.launchpad.net/kubuntu-members-kde4/ubuntu gutsy main at the very bottom and save the file.
3. From konsole run sudo apt-get update
4. Again from konsole run sudo apt-get install kde4-core
5. Select yes to the prompts, you'll most likely get a verification warning, just select yes to continue with that as well.
6. When it is complete, reboot the system and from the login manager select KDE4 as the session.
Hopefully you didn't run into any problems as I did not.
Now should you want to uninstall KDE4 after following the above procedure, then follow these steps:
1. Restart and at the login manager select KDE (not KDE4) as the session.
2. Open up konsole and run sudo apt-get remove kdelibs5 --purge (thats 2 dashes before purge)
3. When that has finished run sudo apt-get install kubuntu-desktop adept kdm
Once the uninstall is complete restart the system. At the login manager the menu should not have KDE4 showing anymore and if you login to KDE everything should be the way it was.
The only things I noticed are that my login manager wallpaper, settings and etc had reverted back to default. Those can easily be restored the way you want them through K-Menu > System Settings > Advanced > Login Manager
As well as the default applications had been reinstalled, so if you uninstalled any of the default programs, you'll need to open up K-Menu > Add/Remove Programs and remove them again.
Hope this is helpful.