Whilst a PP might have had four Davids in her class, you just don't get children with those sorts of names at the moment. Now, if you go for a name like that, you could be unlucky and find out it is about to become super popular again but I think you've got a good couple of days before David & similar become "grandad names" and popular again.
DS has a classic 70s name, is the only one in the school with it (if you discount staff members and about 40% of the dads at pick up!) but everyone knows how to spell it. It does mean you can't get off the shelf personalised stuff but that's never been much of an issue for us.
Other similar names in terms of era whilst being equally solid:
Andrew
Christopher
Adam
Luke
Daniel
Matthew (although I know a handful under 10)
Simon
Jonathon
Nicholas
Peter
Mark
Michael
Of the names you've suggested, James continues to be used in a one in every class/cub pack etc type way although not as popular as Thomas or Oliver or currently fashionable names like Arthur, Oscar, Zak, Noah etc.