Iv'e made a list here that shows a complete list of all the timelines that were created. ( i didn't copy that other thread, i never even knew it existed)
Timeline 1: Origonal timeline, where George is bullied by Biff
Timeline 2: Timeline ceated by marty when he accidentally goes back to 1955
Timeline 3: When Doc goes into 2015 after he frops Marty off at his house
Timeline 4: Doc takes Marty, and Jennifer to 2015 to save their kids
Timeline 5 (1985-A): When Biff steals the Delorean and gives himself the almanac in 1955
Timeline 6: Marty and Doc go back to 1955 to steal the almanac from Biff
Timeline 7: Doc arrives (accidentaly) in 1885
Timeline 8: Marty goes back to 1885 to rescue Doc
Timeline 9: Doc come back to 1985 to pick up Einstein
(Doc probabbly changed the timeline a buch in between, and in the animated series, but we'll leave that out)
Timeline 10: Doc goes to 1931 to find out about the seakeasy arsonist.
Timeline 11: Marty goes back to 1931 to rescue Doc, and accidentally creates Citizen Brown Timeline, which is still, theoretically part of this timeline.
Timeline 12: Marty goes into Citizen Brown timeline and gets the help of Citizen Brown to fix the delorean.
Timeline 13: Marty and Citizen Brwon go to 1931 to fix the timeline.
Timeline 14: Edna goes to 1876 and burns down Hill Valley
Timeline 15: Doc and Marty go to 1876 to fix everything
Timeline 16: Doc and Marty bring Edna back to 1931
Timeline 17: Doc and Marty return to 1986
Timeline 18: Marty's come to 1986 and tell Doc to come with them
Timeline 19 (present): Doc and Marty head off to some unknown destination.
I probabbly forgot some parts, heres a better list: http://backtothefuture.wikia.com/wiki/Back_to_the_Future_timeline
It dosent include the BTTF game timelines though.