@Robert Gentel,
I downloaded No 1.
I now have a lovely 3D painting of my stuffed to the gunwales disk.
I am way too scared to touch anything.
I had a quick look at the Help files...but is there a place you can go to consult re what may safely be removed?
I have an external hard drive,and have moved a lot of non-crucial stuff there, but I had to move iTunes back to the main disk because my iphone (don't ask why, believe me) can only access it from there. This seems to have occupied ridiculous amounts of space...though I am burning and then culling a lot of music.
Would installing more memory help?
The external hard drive is huge, and practically empty, but this seems irrelevant to the main disk.
I clean regularly, btw.