Cleaning up Hard Drive

[characterzero]

So, I want to clean up my computer. I've deleted old pictures, documents, and music. I have deleted un-used apps such as "Quicken" and "Chess."I also removed un-needed languages from certain apps. Will my computer let me know if I'm about to delete something that I shouldn't?

Is there any thing else I can do? I looked online for disk cleaning program...anyone ever heard of "Mac Paw"?

Thanks