Our taxable income, including capital gains, for 2013 was ~$52,000. Capital gains amounted to ~$20,000. I used H&R Block Taxcut to file our taxes (married couple filing jointly).
Because we have a large capital loss carryforward, the program used ~$20,000 of our capital loss carryforward to offset the capital gain. So Form 1040, Line 13 had an entry of minus $3,000 (because our cap loss carryforward was much greater than $20,000).
However, in retrospect, I would have preferred to report the capital gain--as we would have had no tax liability on it--and not used up part of the capital loss carryforward. The reason that we would have had no capital gain tax liability is that our taxable income was less than $72,500.
Am I correct that I could have elected not to offset the tax loss carryforward and still not have had any tax liability for the capital gain? If so, how to I file an amended return to accomplish this objective? In particular, how do I "force" that amended Sch D not to offset the capital gain against the capital loss carryforward?
Thank you.

Am I correct that I could have elected not to offset the tax loss carryforward and still not have had any tax liability for the capital gain?======== It is required that the long term cap. losses have to be used each tax year not skip any tax year at all for that purpose. You were not permitted to simply choose not to use a CL carryforward.you do not have to use a CLCF if you are not required to file a return that year, or
You had zero or negative AGI, exclusive of the CLCF, or
all of the $3K maximum doesn't have to be used, ifyour AGI was reduced to zero by using a lessor amount.

If so, how to I file an amended return to accomplish this objective?===========as mentioned above

In particular, how do I "force" that amended Sch D not to offset the capital gain against the capital loss carryforward?=============as mentionedabove

Thanks very much for the clarification. Comments are very helpful.