I seem to have lost the ability to make directories in Windows Explorer and move existing ones around. Neither can I copy files in Windows Explorer from my CD to my C: drive.

I can still copy files from the CD using DOS. I can also make new Directories using DOS. I can still 'see' the files on the CD from within Windows Explorer

I can still move files from one directory to another with Explorer on the C: drive.

I became aware of the problems after having successfully used 'drag and drop' from the CD and then found when I tried to repeat the exercise with a sub-directory on the CD it would not work. Nor could I then do it at the file level.

I cannot recall anything I was doing previously, other than uninstalling some redundant programs using Control Panel.

I have had a separate problem for some weeks of the computer freezing completely periodically or sometimes seeing the cursor stop moving but is 'released' after a delay of up to 20 seconds by pressing <ControlAltDelete>. I am going to document this in the Hardware section - but thought I would mention it here just in case there was some link.

Thanks in advance for any help that anyone can provide

try running sfc /scannow ... it'll check the integrity of the system files.