Your father would still be the owner, as grantor; but as trustee you now have a duty to maintain and follow his wishes. If you do not want to do so, you must disclaim.
The father can no longer be the owner because he has passed (although he was the grantor). However, that is now largely irrelevant. Also, if @sgeubank does not want to comply with the terms of the trust, @sgeubank should resign as trustee; a disclaimer would be used by a beneficiary to disclaim any right to trust corpus or proceeds.
Your children are beneficiaries and as trustee you have a fiduciary duty to them and they will succeed you in interest.
We don't know the exact terms of the trust so we can't be absolutely certain of that either. Although it is likely, @sgeubank may have the authority to distribute the corpus to himself and terminate the trust. We just don't know whether the children are contingent or successor beneficiaries or whether the language in the trust that relates to them is merely precatory.
