HPF = High Pass Filter (Treble, eliminates the low bassy frequencies from going to the speakers)
LPF = Low Pass filter (Bass for woofers, cuts the high frequencies out)
Off = Full range, this is what you want for you 6x9's
As said earlier. 2 channel amp so your should have 4 terminals to match four terminals on the speakers.
The fuse (cartridge on red cable) goes as close to the car battery as possible.
The earth (black cable) from the amp to the chassis of the car should be as short as possible.(Best to remove the paint where you make the connection)
The wire from remote on the amp goes to remote on the rear of HU. Thus turning on the amp only when the HU is on.
Set the gains on the amp to around halfway to start with and go from there.
Last thing I can think of is to ensure the rear output of the HU (Rear Pre-out) is used. This way you should be able to use the balance and fade on thr HU as normal.