Okay, so the scenario was this: I moved my ship past 1 enemy ship and then bumped into a second. I thought you backtrack until you can fit, so between them in this case. My opponent said no, you back track all the way to your start, then stop at the first enemy ship.

Hard to explain, so lets try an example:

X O O

X bieng me, and O's bieng enemy ships. My move was:

X-O---->O

I thought the rules would end up with

O XO

where I collided but, but he insisted I would end up:

XO O

keeping me in arc of the second ship. I wasn't going to dispute him as he had more experience than myself, but I simply don't think this is correct. Who was right?

You are correct. You backtrack to the first possible spot your ship can fit.

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If there was room between the ships for your ship, then you should only have backed up to clear the second ship. The only reason you would have gone all the way back to clear the first would be if there wasn't enough room between them for your ship.

Thanks, that's what I thought.

Your opponent was a LIAR

...or just misinformed. Either way, you were correct.

This si why I always have a rulebook with me.