I flew the DC-10-30 for many years until just recently, and for a number of operators. The highest flap setting normally used for t/o is 20 degrees, which must be selected on the dial-a-flap wheel.
The fixed flap gates are 15, 22, 35 & 50
I never heared of any performance available for, or anyone trying to use, flap 25 for t/o in a DC10. However, thats not to say that it can't be done!
ex-DCD