Sorted. I have basically done what cedmondson suggested and it has worked; although for some reasons there were approx. 900 files out of 9,000 that it didn't want to import! Strange but not a big issue for me.
I think the lesson learnt is to use the organsier for everything (ie. sorting, renaming, deleting, etc) or not at all.
@ GaryK26 : if you have odd disconnected files then you can reconnect them but browse for the files yourself rather than letting PSE search. This is what I had started to do but as I had deleted some 400 images (

) all in windows it was somewhat of a tedious task; hence my need to 'rebuild' the catalogue.
Thanks for input, think I'm just about there now.