I did enjoy dinner thanks, and yeah I would just use gnome disk tool, it should install just a few packages and not install the whole gnome desktop. a lot of people get thrown off when someone suggests an app that is mainly from another DE of linux (desktop environment) they think they have to install another whole linux distro just to use it. Nah, its much better then that trust me. And its possible there may be something wrong with your disk, I wont know until you do the check. It may not be Kubuntu, but I have to rule everything out. Usually when I see the issue you describe it usually deals with windows drive detection (I had a similar issue myself) so I had to eliminate that. It could be your drive, how old is it? I would not blame Kubuntu if the disk is old or something like that, wear and tear is a factor for any OS.