I start with an apology! - I thought I'd update this post and saw that you had all posted additional information... :-[Not sure why I haven't seen notifications, probably an over-sight on my part, so sincere apologies for not acknowledging sooner to Clairec666, Marmalady, Galium and Beeonthebay.
Clairec666 & Beeonthebay - thank you for confirming the name. It's good to have others have a look as sometimes you can wish something to look the way you want it too.
Marmalady - I had forgotten about the 6wk rule, so thank you. It's a bit naughty really as children were brought up with the incorrect birth date. - It's interesting though, as I have always thought that the birth cert reported 'the true' dob... you live and learn.
Galium - Great piece of info... I had noticed the signature and just thought it a coincidence - I've others with the same registrar name, so now I know... very interesting.
So, as a final update, I received the Birth and Death Certs for Harold Greenwood Jones. His birth was as expected - no fathers name

- Interestingly, his mothers maiden name isn't recorded either...

Don't suppose I'll ever know who his Father was, there are a few Greenwood's (if indeed this is a clue as who to his Father was...) who could fulfill the role but without concrete evidence it will remain on the 'mystery' pile...
Harolds death was reported by an Aunt, but no immediate family...
I think I have probably gone as far as I can with this for now...
Really appreciate the help I have had with this leg of my family - sincere thanks to those of you that have been involved... Great Forum, lots of experience and fabulous for helping me to think outside the box with my regularly elusive ancestors!

Thanks for reading.
Lisa