My kids are now 20, 19 and 16. Ten years ago they were chased, harassed and on one occasion when being chased, my son was touched in an attempt to grab. This was all perpetrated by a psychotic neighbor who thought this cottage-like street was "his". I never had him charged as this happened at my brothers place and my brother begged me not to charge him as it would escalate the situation between them... and I respected that. Can this former neighbor be charged criminally today? Or is this ancient history?

I think it would be ancient history. Then there's the issue of witnesses, signed affadavits, etc.

Tick

... they were chased, harassed and on one occasion when being chased, my son was touched in an attempt to grab.

...

Can this former neighbor be charged criminally today? Or is this ancient history?

What would he have been charged with back then? Criminal touch football? Sounds awful petty to me.