I'm not gonna rank the rest. Didn't like BO1 and had way to much frustration with MW3
If you look past DC, OMA and some unfair killstreaks, I find MW2 the best. The maps were amazing (and for the record the campaign was as well). Many memories with that game that BO1 and MW3 couldn't capture.
Then again I was a much more avid COD gamer when MW2 came out since it was the first COD I played. Might have just grown old on me by BO1 and MW3, but giving BO2 a chance.