I don't care what anyone says to be a Contrarian, Sean Connery and Roger Moore were the best.
Their respective times (60's, 70's and early 80's) and the look it gave off on the screen also helped them. James Bond was meant to be a cheesy melodrama. A average build man with sort of average fighting skills who gets himself into all sorts of situations and gets out of them clean. Kind of like Forest Gump. The new ones who are trying to make Bond into Bourne (as already mentioned) or the 'Taken' guy, is just overkill.
If you can't make it work anymore with a average looking charmer, in his mid-40's, hair chested guy -then just don't make anymore Bond movies. We don't need Bond to be an athletic, martial artist killing machine.