Totally agree - it's pretty much what I was saying. You wouldn't say 'well I hate small spaces and I collect knives' if they asked you an interview questions about your likes and dislikes! There is clearly a balance to be struck between 'being yourself' and showing your 'best side'. It's good to stay away from emotive subjects (religion/ politics etc) as they can bias an interviewer, though of course nowadays some interviews deliberately try and provoke a situation by asking awkward questions on these areas!
In summary, the conclusion you are coming to is that this isn't black and white - you don't want to be showing warts-and-all but you also don't want to lie or say nothing for fear of 'giving something away'. There are shades of grey and it's down to you to judge the situation and come up with what you believe is an appropriate response. If you are concerned about how you would handle an interview, why not get some practice through one of the many courses around?