I absolutely agree with Francesco: you really do need to get your hands on their first two albums. And that is not an expensive prospect. Just visit A & B Sound's online store (www.absound.ca) and you can hook yourself up with both of them for somewhere around $10 each U.S. (maybe less, actually). However, having said all of that, I do have to admit a couple of things up front:

1) I don't own the Ballads compilation (yet)

2) HS's ballads are possibly my favorite songs of theirs. Stuff like "Slowly Slippin' Away" and "Honestly" are nothing short of phenomenal, IMO. The thing is, though, it's not JUST their ballads that are incredible. That's why I'd recommend picking up their first two albums before you get the Ballads album. I am positive that, if you do, you won't be disappointed. Hope this helps.
Don