Hi squigs, and a big warm welcome to the forum.

It's great to have you aboard, we all love to learn new things and tinker here.
Re your mowers,

on a good score there, and all in running order as well.
Re the first mower in the group, I would guess that grumpy is correct is saying it is an early mark of Villiers engine and could possibly be an english manufactured machine.
Does it have any identifying decals or labels on it (or the catcher) as to its make?
Re the Victa Imperial, there should be a sticker on the engine cowling somewhere indicating what series engine it is. this will come in handy if you require parts during the restoration. Also, if you are doing a 'ground up' resto, when you have the cylinder reel and bottom blade disassembled, that is the time to check the reel bearings and have the reel and bedknife (bottom blade) sharpened.
There appears from the pic that there is plenty of meat on the reel. By the way, it is preferable to paint the reel, prior to sharpening.
Re the Webb, can you please post more pics showing it from different angles?
Once again, squigs,