For starters, the Education department, give power back to the states.
Then, the Energy department, just leave the Atomic Energy commission to regulate nuclear material. They haven't solved anything else.
The Welfare Department, this should go back to the states also.
The Justice Department. I don't see where this is absolutely needed at all.
Amtrack, if trains were efficient, they would still be operating by private companies.
Social Security, give all the "borrowed" money back and privatize it. It would make more money over a lifetime of investment.
IRS, I would eliminate income tax and replace it with tariffs on foreign goods. If more money is needed maybe a 1% national sales tax.
ATF, not really needed anymore. Laws are in place regulating alcohol, tobacco, and firearms. Local people can handle this.
Anything else. I sure I only touched on a few.