What is the version of LR and your OS?
Deleting images does not make LR hang. It only gets you '?' on folders missing and '!' on photos missing because LR can not access these any longer and they are lost. You know that LR needs the originals if you want to do something with the images in LR, do you?
Please explain the Serious PC problems you are/were having and "Who" told you to "Make a lot of space" on your drive.
The deleting of a 100GBs of image files should not, will not, have any affect on whether LR, or any other program installed on your computer, starts up properly.
Thanks for the comments. After doing a bit of further investigations, I realised that the file deletion was having nothing to do with the issue (I do have two, external drive backups of the images). As it happens, I got a message offering me an update to the July version of Lightroom. I've just done this and now the application opens fine. I've removed the links to the deleted files from the LR catalogue. All seems fine.
Thanks for the responses. Ed ...