It's either that, or save the clock tower, it's your choice. Granted, if you help save the clock tower, then future generations may forget when it was struck by lightning, and of course that'll strand Marty McFly in the past forever, but we digress.

There is a massive and mind-bogglingly complete Back to the Future timeline on Wikipedia that is the effort of some seriously fanatical fans. It details events that were cut from the original scripts (for instance, did you know that Doc Brown and Marty met in 1983 when Marty showed up to sweep the Doc's garage?), the animated series, and meticulous picking apart of the films themselves. It's a real labor of love, and it's in danger.

Wikipedia has some pretty strict policies regarding verifiability, and that leaves the BTTF timeline somewhere between limbo and a hard place. Check out the discussion page where people are chiming in on whether to keep the article or not. So far is a resounding "keep it!" but if you want to give your own opinion on the matter, roll up your sleeves and dive right in. Wikipedia is by the people, for the people.

My two cents on the matter is "keep it." But it goes a bit deeper than that. I've probably seen Back to the Future at least 20 times, and it's ingrained into the folds of my brain (perhaps that explains a lot). This timeline is really an amazing work of fans that detail everything you could possibly want to know about the history of Mill Hill Valley, Doc Brown, the McFly clan, and anything that even comes close to being touched on in the films (Pepsi Free? Invented in 1955, thank you very much). It's a tribute to the appeal of these movies, and a great demonstration of how fans can keep something alive long after the last bits of popcorn have been swept up.