But I can use porta with outputs.

PORTA = 2
Pause 400
PORTA = 4
Pause 400

This makes the two leds turn on and off alternatively.

So if the pic doesnt have porta, why does this work?

I have defined pin 0 as input and pin 1 and 2 as outputs.

Input PORTA.0
Output PORTA.1
Output PORTA.2

And I'm a high school student, I don't have a degree in engineering, so I don't have a clue what the datasheet says.

Can you please explain that about disableing analogue functions on multiplexed pins?

Thanks again
/Henrik