How would an active crossover be an advantage for this system?

[Trepkos]

Kenwood eXcelon KDC-X791
Phoenix Gold RSd65cs 6-1/2" 120W Component Speaker System
Profile AP1000 1000W 2 CH Amplifier (2 ohm Max Rating)
2x Kicker CompVT 12" 2-Ohm Subwoofers
Hifonics TitanTxi1008D Class D Mono Amplifier
American Accesories 4gauge amplifier wiring kit
JL Audio Dual Amplifier 4gauge Wiring Kit
KnuKonceptz Konfused Distribution Block
KnuKonceptz Krystal RCA Cables
1.86cu ft Sonic Boom 2x 12" Subwoofer Enclosure

Any recommendations on one and how would I wire it?

[genxx]

Can't go active unless you plan on buying another amp for starters. You need 4 channels to run the front speakers. I do not know what the abilities of the Kenwood. If it does not have atleast a 2-way x-over built-in and some EQ ability you are going to need some external processing or a new HU.

I say two way meaning it will do high and mid. Then you would have to use your sub amp x-over it has one built in. You need to lots of research and reading before you even think about going active.