That my problem. I don't have any friends who play bass or the guitar.
Well where about are you located in JHB?
Surely a forum member near you/
the shop would be willing to help out (myself included)
Humbucker pickups are usually dual coil like the Musicman style bass pickup or a soapbar humbucker (You also get single coil soapbars... It gets confusing)
the P-bass pickup can also be considered dual coil but it is actually just a split single coil. Both of these alone cancel out the hum associated with single coil pickups whereas a J-Bass uses two pickups on at the same time to achieve this.
Each of the three types sound different from one another and also basses come with a mixed variety of the pickup configurations (P, PJ, 50's P, J, JM, S, SS, SM, JS etc...)
Active requires a battery to work due to an on board preamp which boosts the signal.
Passive is just the raw pickup running into the amp.
Some come with a Push/Pull volume or tone knob that acts as an active bypass meaning you can switch an active pickup to passive (Like my GB35A bass before someone screwed up the wiring...)
It's all up to you though... Neither is better or worse, it's just about what you prefer... Like I said, I own an active bass with a Musicman style pickup in the bridge and a J bass single coil in the mid/neck position but my favourite bass sound is the middle position thump of an Epiphone Thunderbird bass followed by a PJ-bass middle position... It's all about what you dig the most...