Dude, You dont want a DV sequence, pro rez those hd clips, work with the higest rez you got…
is this for a Feature film or Client? Make a double copy of the dv footage, put a light blur filter and extend to the edge of the HD frame size…Boom!
I shoot the pannasonic DVX 100b on squezz mode, as my 2nd or 3rd camera, then it fits HD Perfect.