In reference to the kayaks, rachet straps aren't a good idea. You don't want anything more than hand tight really. Ratchet locks have the risk of bending and/or cracking a boat if over tightened, especially if you have a fibleglass or carbonfibre surf boat!
Stay away from rope, it doesn't offer enough grip and things might slide forwards/backwards.
Flat straps with a friction lock on the end are perfect.
Loop over the boat once and lock off, tying the free end around the roof rack ensures nothings gonna be flapping around in the wind.
I had both my kayaks (whitewater and surf boat) on top of my car secured in this method with 1.5" flat straps on a 300mile round trip and they were fine both journeys.
Can't help you on the surf boards, have you not got a local surf shop near you that you could ask in?
edit: put the kayaks upside down on the rack, they won't fill with water if it rains then
