64-109 are all fillers that are include the "Bounto" and that is all irrelevant to the actual storyline. You may find other random filler episodes assorted throughout the anime but this is the most prominent one.
The last part of 109 is important though so you may want to watch maybe the last part of it.
Another filler arc, which is still irrelevant to the main storyline, is way better but it spans from 168-189.
If you want to see for yourself, look here:
http://en.wikipedia.org/wiki/List_of_Bleach_episodes
