Осталось осталось после конвертации Lubuntu в Kubuntu

Нет, различий нет. Вы можете просто

sudo apt-get purge --auto-remove abiword abiword-common abiword-plugin-grammar abiword-plugin-mathview  ace-of-penguins audacious audacious-plugins audacious-plugins-data blueman  chromium-browser chromium-browser-l10n chromium-codecs-ffmpeg  elementary-icon-theme esound-common galculator gdebi gdebi-core  gecko-mediaplayer giblib1 gnome-icon-theme-full gnome-mplayer gnome-system-tools  gnome-time-admin gnumeric gnumeric-common gnumeric-doc gpicview  gtk2-engines-pixbuf guvcview hardinfo indicator-status-provider-pidgin leafpad  libaacs0 libabiword-2.9 libaudclient2 libaudcore1 libaudiofile1 libbinio1ldbl  libbluray1 libbs2b0 libcddb2 libcompfaceg1 libcue1 libencode-locale-perl  libept1.4.12 libesd0 libexo-1-0 libexo-common libexo-helpers  libfile-listing-perl libfluidsynth1 libfm-data libfm-gtk-data libfm-gtk1 libfm1  libfont-afm-perl libgdome2-0 libgdome2-cpp-smart0c2a libglade2-0 libgmlib0  libgmtk0 libgmtk0-data libgoffice-0.8-8 libgoffice-0.8-8-common libgringotts2  libgsf-1-114 libgsf-1-common libgtkmathview0c2a libguess1 libhtml-form-perl  libhtml-format-perl libhtml-parser-perl libhtml-tagset-perl libhtml-tree-perl  libhttp-cookies-perl libhttp-daemon-perl libhttp-date-perl libhttp-message-perl  libhttp-negotiate-perl libid3tag0 libimlib2 libio-socket-inet6-perl  libio-socket-ssl-perl libjpeg-progs libjpeg-turbo-progs liblink-grammar4  libloudmouth1-0 liblwp-mediatypes-perl liblwp-protocol-https-perl  libmailtools-perl libmcrypt4 libmenu-cache1 libmowgli2 libmpg123-0  libnet-dbus-perl libnet-http-perl libnet-ssleay-perl libobrender27 libobt0  libonig2 liboobs-1-5 libopts25 libots0 libpisock9 libresid-builder0c2a  libsidplay2 libsocket6-perl libtar0 libtidy-0.99-0 libtie-ixhash-perl  libtimedate-perl libuniconf4.6 liburi-perl libvdpau1 libwebcam0 libwv-1.2-4  libwvstreams4.6-base libwvstreams4.6-extras libwww-perl libwww-robotrules-perl  libxfce4ui-1-0 libxfce4util-bin libxfce4util-common libxfce4util4 libxfconf-0-2  libxml-parser-perl libxml-twig-perl libxml-xpath-perl libxss1  lightdm-gtk-greeter link-grammar-dictionaries-en lm-sensors lubuntu-artwork  lubuntu-artwork-12-04 lubuntu-core lubuntu-default-settings lubuntu-desktop  lubuntu-icon-theme lubuntu-software-center lxappearance lxappearance-obconf  lxinput lxkeymap lxlauncher lxmenu-data lxpanel lxpanel-indicator-applet-plugin  lxrandr lxsession lxsession-edit lxshortcut lxtask lxterminal mplayer2 mtpaint  ntp obconf openbox openbox-themes osmo pcmanfm pidgin pidgin-data  pidgin-libnotify pidgin-microblog plymouth-theme-lubuntu-logo  plymouth-theme-lubuntu-text python-pysqlite2 python-xklavier scrot sylpheed  sylpheed-doc sylpheed-i18n sylpheed-plugins synaptic system-tools-backends  transmission ttf-lyx uvcdynctrl uvcdynctrl-data wvdial xfburn  xfce-keyboard-shortcuts xfce4-power-manager xfce4-power-manager-data xfconf  xfonts-100dpi xpad xscreensaver xscreensaver-data

удалить все из вашей недавней установки Lubuntu.