I have read the 2008 and the 1988 version. The 2008 version is the 1940 version with commentary by accountants in added chapters to bring the book up to current methods and to discuss what changed in the world since the writing of the original 1940 book. The 1988 book is not by Graham as he had died in 1973, but primarily by Syndey Cottle with the blessing and imprimatur of David Dodd. I have not read either the '34 book nor the '62 book.
The fact that modern users felt obligated to reissue the 1940 book and not the '62 book tells me they felt the 1940 book was better.
The differences between the 1988 book and the 2008 book are pretty stark. If you have never done security analysis before and you need technical skills, then the 1988 book is better. It is more of a "what" book. If you have excellent accounting skills and have done security analysis, then the 1940 book is better as it is more of a "why" book.
The 1988 book is a bit more step by step view of what to do with ratios and so forth. The 1940 book is more of an attitude toward viewing and understanding relationships inside and outside the firm as well as the role of the statements and their notes. Really, security analysis is notes analysis as the statements are inadequate for the purpose.