An 'arranged marriage' is one where the parents, other relatives, or a matchmaker chose the partner for someone. The 'arranged' here does not refer to planning the wedding and reception - it means the traditional type of marriage in many cultures where the partner is chosen for someone by family or a matchmaker.
If you met and fell in love with someone, and the relationship developed over a period of time, this is not usually considered an arranged marriage.
As for 'living together', for a common-law application in general the couple has to live together for 12 months to qualify. But form IMM 5490 does not mean this when they ask about whether the sponsor and applicant have lived together. You should definitely put down the times you and your wife have stayed together somewhere on this form. Questions 24 and 25 might cover it.
For question 27, you could put 'no' and for your explanation say that you returned to Canada after your wedding, but that you and your wife did stay together in her parents' home for --- weeks. Or you could put 'yes' and list all the times you have stayed together, even if it has only been for one week - or even one night.
If you read appeal cases, you will see many examples where the judge thought that even short periods spent together should have been listed in question 27, and the answer should have been 'yes'. Make sure it is very clear in these questions that you have stayed with each other.
