Agree. Depending on the type of interviews, you might actually get several questions to which no one could possibly have an answer - like how many golf balls you can fit into an airplane, etc.

I don't think that it would be a good idea to be grinning when faced with these questions. Best to keep your composure and make an educated guess and explain your reasoning.

I'm not saying it's impossible to answer, I'm just saying that it isn't something you can just pull out of your head in a few seconds. So you'll just have to make an educated guess and make estimates. Unless of course you are capable of making better than average mental calculations.

A face to face interview or a phone interview ?
Maybe it was a preliminary interview or something ?
But honestly even for a phone interview it seems really short. Best is you try asking other candidates who have gone for the same interview for comparison.

It shouldn't be a scary event. The best way to be confident is by making sure you are very well prepared for it.

If you are worried about your language skills, then practice presenting yourself and answering the most common questions.

Maybe you can tell that your previous job made you discover what you really wanted to do and what you like less in a job. You'll need to add real examples though, otherwise it's not going to impress the interviewers.
Wow I've never had this type of question before. Mind sharing which industry/position you were interviewed for when they asked you this ? Maybe it's a position/industry that requires very good people skills ?

Btw did you get it right ?

Ok well thanks for sharing, and good thing you got the answer right.
Why do you think that the issue would be relevant in a job interview ? I honestly don't see why you should bring it up at all, and personally I wouldn't say yes even if the interviewer asked (which I highly doubt).
I don't think it's a good idea to answer it that way. Simply because the next most likely question would be :
"Why do you think your company won't continue your contract ? " Won't you seem doubtful of your own employability ?
I suggest saying things like : The old job wasn't what you wanted, or you want to try out new roles and develop your skills in other areas that won't be possible in the old company.

Well from what you said it seems that you are through to the hr interview stage, but it's never certain until you get a confirmation from hr. Just remember to follow up if you don't get any news by next week.

And anyway about him 'seeming' to not know about things is probably just a way to let you do most of the talking, since this level of the recruitment process is mostly just to get a first contact with the candidates and evaluate their communication skills.

Best would be to choose a subject that can demonstrate to the interviewers your skills, knowledge and advantage over other candidates.

Basically the company has given you a golden chance to prove yourself when they let you choose the topic.
You can talk about your internships, work experience, co-curricular activities, projects etc.

There's the salary guide report in the salary discussion thread, maybe you can have a look at that.
Best would be to see if you can chat with some of the staff at the company to know what range would be suitable.

As a fresh graduate, it's not advisable to demand for a specific salary. Usually companies have specific pay scales for freshies and it's most probably going to be applied across the board. If you're asked the question on salary expectations, say what you have gathered from your research and then turn it around on the interviewer to ask how much they are willing to pay for this particular position. It shows that you're also considering the other side of the table as well and not just your side. It's wise to be well informed on the salary range you can expect, to avoid being shortchanged.