Hi again, thanks for all the help thus far...
To give idea of the files etc, they are mostly avi files, i.e, movies ive downloaded which obviously take up a significant chunk of space. I noticed the problem on my desktop. I use a download manager to save everything onto my desktop and usually delete them from the desktop once I've watched them. When I changed hidden files to be viewable, my desktop was filled with loads of videos I have deleted from the past.
In fact, as I've just finished writing this I've realised it might be the download manager. I use 'Free Download Manager'.....could this be an issue??
I've now deleted all these hidden files ive found and seem to have got rid of them all, but I'd like to find out what caused this if possible to prevent it from happening again. (I am aware of the concept of hidden files, and I am only refereing to files I have acquired, not any system/docu files)