Depends on how simple your case is. If you have a simple buy at X and sell at Y you are pretty much correct.
If you say - mined your coins back in 2011 - and never did any accounting of that income at that time, if you want to be able to claim capital gains vs. regular income you are going to find a pretty clued-in tax attorney to do such a thing.
Even worse if you were an early adopter and started spending coins/trading with folks back when it was all magic internet money. Did you account for those 50BTC you sent as a tip to that software dev you enjoyed? It was $100 at the time, so I doubt many people were keeping careful records.
What if you started trading on mtgox or bitstamp or whatnot 5 years ago? Did you account for all those trades as income at the time even if you never cashed out USD to your bank account?
All in all it depends on your situation.