df1 was nice, but that was before my time online, so i went through SP once and that was it.
played df2 for a veeery long time, great game
got df:lw too, but it just has no chance against df2
never played TFD but im terribly biased against it, just the same crap as dflw, only more of it
BHD is also great. not as great as df2, but still a very enjoyable game
so my vote goes to df2 and bhd