Both are correct, head to and head over to. But we sometimes say "head over to" to give the impression that our destination is close by. For example, "I'm going to head over to see my friend now". Your friend is close by. However, "I will head to the shops". Those shops could be anywhere, but if you said "I'm going to head over to the shops", it gives me the impression that the shops are really close by.
"Off-the-record meeting" means that the meeting is not official and therefore the media won't report it, whereas an "on-the-record" meeting means that the meeting is official and the media will report it.
I hope this helps!