If you think about it, this and that mean nearly the same thing in English. They both mean "the specific item, which I am likely pointing to or otherwise indicating". The only difference is the relative nearness of the item. So if you need to make a point of the item's proximity, then you use ĉi with the pronoun. Otherwise... what's the difference?
Tiu means "that one", or "that (followed by a noun)"
Mi ŝatas tiun kantiston = I like that singer (not * Mi ŝatas tion kantiston)
Tiu estas la plej granda besto = that one is the biggest animal
Tio estas interesanta = that is interesting
Tiu estas interesanta = that one is interesting
I have trouble, this guy's "T" sounds like a "D" to me on "Tio" again. His "gxia" sounds like "ge ot" with a "t" on the end. I had go searching again and it still didn't sound right. The rendition above sounds alot clearer than the lesson version. I can accually tell the words on this rendition. I hope they'll put this version in the lessons and remove the other one.