A tech guy told me that I should use ccleaner once a month because of the way the hard drive stores data and when the data get removed. The drive becomes more defragged or whatever because the files are all over the place and shorten the life of the hard drive. Does CCleaner help prolong or shorten the life of the hard drive it you use the program too much?
No.
To clarify, it can cause increased fragmentation by virtue of deleting files in the middle of the drive.
Essentially, when files are written to the drive, they're written in blocks, so files A B C D E F and G might look like this
AAAABBBBCCCCDDDDEEEEFFFFGGGG
but now you've deleted file B and file E, so you're left with
AAAA____CCCCDDDD____FFFFGGG
Now you write file H to the drive, but it's small, so you you have
AAAAHHH_CCCCDDDD____FFFFGGGG
here's where the problem starts, file J is written
AAAAHHHJCCCCDDDDJJJ_FFFFGGGG
now file J is fragmented because it wasn't written contiguously on the drive. Over time, as more files are created on a drive, this tends to happen more and more, which is why we defragment. You can prevent fragmentation to a degree by defragging your free space, which defragments your files, then attempts to move them all into one contiguous block of files, so that new files are not written inside the block causing more fragmentation.
Unless you're running wipe free space with a 35 pass algorithm a few times every day with CCleaner, I can't see it shortening the life of any platter hard drive in a measurable way.
Based on the forum you've posted this in (CCleaner for Mac), I don't think you need to worry. Mac OS X has a daemon that runs silently in the background performing maintenance tasks, including disk defragmentation. Newer Macs use solid state hard drives (SSD) which do not suffer from fragmentation problems as described above. They do, however, suffer from a limited number of IO cycles - I still wouldn't worry though; they're more resilient than most people think.