Deleting old local recordings in groups vs each one

Welcome to the Zoom Community, @Sunsethill29.

What type of computer are you using?  On Windows, you'd just go to the folder where they are stored, select them all, and press the Delete key.  There's nothing special about them... they're just folders with files in them, as far as Windows is concerned. 

If you are hoping to free up disk space, remember to clear out your Recycle Bin.  OR you can optionally hold down the SHIFT key when pressing the Delete button - Windows will ask you if you want to permanently delete these files/folders, and if you accept it, the files will be removed, not just moved to the Recycle Bin.  Be sure you are not about to delete anything you'd want to keep...once you accept this step, they're gone.