Imdb votes, and so its top list, lost of value (and so of my consideration) a few years ago. Reason: the majority of imdb voters it is teenagers who seen a grand total of 250 movies in their short life, none of which outside the imdb top 250 list. There is no way they see or vote any movie released before of year 2005 unless already in the imdb (or similar) top lists.
As an example, I would not consider the votes of anyone who does not seen the holy mountain
http://www.imdb.com/title/tt0071615/ , it got votes from 10,260 users and 102 reviews, and it is released in 1973.
Compare with the dark knight rises released weeks ago already 209,000 votes and 1598 reviews (and ridiculous vote 9.0 - evidence those people seen no any movies before of that).
In general the imdb user reviews are more useful than the vote, but just for not-popular movies.
An example is in the anime - the tv movie episode Lupin III Rupan Sansei: Episode 0 ,
http://www.imdb.com/title/tt0827737/ of 2002, it got only 115 votes and 2 user reviews, but the vote is 8.6 and reviews are good. In fact, this is one of the best Lupin III movies ever, but no way you discover it from imdb top lists.