double checked and since 1967 only once have 7 DBs (S + CBs) ever been drafted in the 1st round (1998). so 10 would be the most ever for a long time...
(I checked on theredzone.org... I did notice that they list darrell green as a C instead of a CB though :P)
http://www.theredzone.org/draft_history/
1983 draft - 3 HoF QBs (elway, marino, kelly) chosen in the 1st round, 6 1st round QBs taken (most ever on both counts) and 1 head coach (QB Gary Kubiak) was also taken in the 8th round.