Wow, thanks for that link, MdX5! That sure cleared up some questions for me. I am playing around with the sizes, and so far I am going by what I am being recommended at this moment.
Your recommendations are great, Morty, thanks. I guess it's a matter of finding out if these tire sizes (215/60/17, conservative and 235/55/17, a bit more aggressive) are available for the wheel (17 x 7) that I have my eyes on. I am kind of looking for a tire with a lip guard to protect the side of my wheels because I am prone to scratching them when I sometimes turn too sharply at curbs. The tires that I was recommended, the Falken Ziek S/TZ 1, had them, but the reviews I have read sorta scared me from getting them.