UNIX Permissions & Directories

Earlier I migrated my internal drives from an older file-system to ReiserFS v3 and am still learning UNIX permissions so do bare with me. I understand how permissions are broken down but ran into an issue earlier.

I had the idea of recursively setting 644 (rw-,r--,r--) to the contents of one of these drives and grant execution privileges to choice files such as shell scripts and binaries used to launch games. However, I found that none of the files or directories were accessible. The drive's root contents were listed but could not browse or access any of the files/directories deeper than this. I finally found through trial that I could open files only if their parent folder had execution privileges. My questions are whether or not this is normal and if there is any way to recursively set permissions to only directories using chmod/chown.

Any help would be appreciated, I'm in no rush.

find / -type d -exec chmod a+x {} \;