Change the size of the form element for content title
You don't have the options of choosing your title field lengths in standard D7. 
However, there is a module that lets you change that:

https://drupal.org/project/title_field_ui

The only problem is, that the module is only in alpha and not widely used. On the other hand, the module author is very reputable, so I'd give it a try. 

Other solutions have been discussed before:
Change / Increase the node title length