Yes first thing is your wife needs to become a naturalized citizen, in order to petition for her parents. The parents will have visa immediately available and can immigrate as soon as the paper work goes through.
her parents would be considered:
QUOTE
Immediate Relatives of U.S. Citizens (IR): The spouse, widow(er) and unmarried children under 21 of a U.S. citizen, and the parent of a U.S. citizen who is 21 or older.
The parents then will have to petition for her brother, this makes her brother: (Takes about 2 years)
QUOTE
Family Second Preference (F2): Spouses, minor children, and unmarried sons and daughters (over age 20) of lawful permanent residents. (114,200) At least seventy-seven percent of all visas available for this category will go to the spouses and children; the remainder will be allocated to unmarried sons and daughters.
If your wife were to petition for her brother after she becomes a citizen it will take much (6 years) longer in this case her brother would be considered:
QUOTE
Family Fourth Preference (F4): Brothers and sisters of United States citizens, and their spouses and children, provided the U.S. citizens are at least 21 years of age. (65,000)
See:
http://travel.state.gov/visa/immigrants/ty...types_1306.html