Most free stuff is fine misty, and most "freeware" has an upgrade version that can be purchased...well known freeware bug finders such as those mentioned have a reputation they must fiercely protect so they usually can be trusted.
What many people tend to not do is not uncheck the pre checked boxes when they download "freeware" and end up with all sorts of stuff they don't want cluttering up their PC....especially tool bars or search engines which can be challenging to remove once embedded....
