Just starting here, is it okay for me to use different finger placement for chords than what video is showing me?

Example, video is telling me for A Major chord use my index, middle, and ring on 2nd fret. I just can't do it, but I can get the A Major chord with my middle, ring and pinky finger.

It seems easier for me to use my pinky even on the D major chord even though DVD is saying drop the middle finger to the 1st string.
For A, yeah, that's fine. A lot of people play it with those fingers. But it's best to be able to play it both ways in case you need to do different variations on the chord.

For D, though, you're really going to want to be able to use our middle finger on the first string because you'll want your pinky to be free for variations on the D chord like Dsus4 (pinky on the third fret).
Of course it's alright, as long as it's the same chord. It's just the way way most people learn it.
As swarley said, how you do the A is fine, though you really should use your middle finger on the first string for the D chord as there are times when you'll want your pinky on the third fret and your middle finger on the second.
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Playing the A that way will really help when you get to A shape barre chords.
D chords are great fun. I learnt to play with a barre on the 3 strings and middle on the B string. Then I tried playing BADGE and realised I needed to play with pointer on the G string, middle on the e string and pinky on the B string so as to have my ring finger free for the run-down. Quite a few songs use that technique.
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you are going to have problems when you start going from D to Dsus4 back to D.

for the A i just barre the 2nd fret across the 3 strings but i can bend the 1st knuckle on my fingers the wrong way (i`m a freak) so i don`t touch the high e.

for the E chord you should be fine, this was the way i`d introduce students to moving barre chords.

have you damaged your index finger in the past, so that it`s giving you problems making chord shapes
That's how I play A major, I would do the same for E major if I knew there was a E shaped barre chord coming up
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For the A, the way that you want to play it is really common and it's fine to do that however, you'd be better of learning both ways just in case you need it for a song or something. For the D though, you might have to use your pinky plus the D chord for chords like Dsus4 so you'd be better off following what the DVD says for the D chord.

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