One of the Time Lords is a female known (colloquially) as "The Woman". That is not her name. We do not know who she is but we refer to her as such. She is the one who talks to Wilfred Mott and guides him.
The other Time Lord's identity is never revealed. We do not know who that person is.
Outside of guiding Wilf and being important to the Doctor on a personal level. The Woman has no other important role. The other Time Lord has no important role in terms of the plot.
Russel T Davies has indicated that to him The Woman is the Doctor's mother, and gave direction to the actors as such. However, it is never explicitly stated or confirmed by the characters in the TV show.