To clarify, I am still using KDE (Kubuntu specifically) but I also have Gnome installed. However, when I log in, my plasma desktop shows up for a few seconds, but then switches to the Gnome desktop. The plasma widgets disappear, the icons change, and the right-click menu is GTK themed and has the Gnome options rather than the KDE ones.
I've been messing with a lot of options over the past few days, but I think that this probably happened because I removed a lot of native apps (Amarok, Dragon Player, Movie Player, KMail, KTorrent, Transmission, and maybe a couple more).
Any ideas on how I can revert back to my KDE plasma desktop without a complete reinstallation?