Well I think that I've made sense of this post (just!). The charge will almost certainly depend upon the injuries suffered by the 'bloke in his mid 40s'. See paragraphs 9 to 19 (in the link below) for the definition of 'Common Assault'. See paragraph 45 onwards for the definitions of 'ABH', 'GBH' and 'GBH with intent':
http://www.cps.gov.uk...s_against_the_person/
When you've worked out, based upon the injuries, what the likely CHARGE will be, post here again (telling us which charge applies) and we'll try to indicate the likely SENTENCE.
Chris