you are missing one slight thing, how can someone differentiate - tell apart say one version of 'A GAME' and 'ANOTHER VERSION OF A GAME WITH A VERY SIMILAR NAME' say I have 1951a and I have 1951b. I cant go running each one. Double checking I got the name right and then delete. Then run the next. Over and over. A lot of 'GAMES' have the exact same name save for an additional letter on number that is gibberish to you me and Jez over there.

You have a . . . unique . . . way of seeing things, CJH, but if you're going to scold me for "doing it wrong",
READ MY ACTUAL WORDS AND PROCEDURES instead of skimming and mischaracterizing them.What
YOU are missing is that MAMEUIFX has the list of filenames associated to the game titles/variants including parent/child sets.
If you want the fast shoot hack variant of Galaga, you'll need the child rom "galagamf" (indented) and the parent "galaga". (not indented)

When you combine it with History.dat, info.dat, and progetto snaps, you don't have to launch a game to see if it's the one you want.
The problem with your approach is that you you start with all files in the roms folder and remove the ones you don't want.
As I said before, it's easier to add 200 files to a folder than delete 8,500+ files and hope that you don't break another game along the way.
And , I don't know about anyone else but sometimes my hard drive takes a long time to access said folder.
Not sure why that would take a long time -- even for my old EIDE drive only takes two seconds when it first loads the folder.
Pull the Archive folder up then right-click to copy the desired file and right click on the roms folder in the left column to paste.

The folder view remains in the Archive folder -- no reload time required.

If Windows Explorer isn't behaving that way for you, open a second Win Explorer window so one is in roms and the other is in Archive. Alt-Tab between them to copy/paste.
Fear not tis all in hand.
No
fears here -- my methods are the easiest, fastest, and most future-proof that I've found for my use. YMMV.
It's your time to spend as you see fit, with whatever you want in your hand

, just don't assume that your solution fits all.
I do wish you luck, and hope that your method allows for the occasional renaming of romsets that happens in MAME as new/better dumps become available -- I let MAME do that work for me.

Scott