It's definitely good - I wouldn't be without it.
You can bar from entry any cookies (e.g. from Microsoft, Google, Yahoo, MSN, Adobe etc.) that you don't want. Or permanently keep those (such as from this site) that you DO want.
Your start-up menu, BHO & running programs list can be managed. You can get alerts when changes to your system are attempted with an option to disallow them.
Other free progs do similar jobs (separately) but WinPatrol is easier to use.
Bill P who makes it is very approachable and helpful and there is a good users forum.
One edition - about a year ago - had memory leaks and problems but, as far as I know, that was sorted out.