1) The times on the website are average for 80% of applications. Some applications may be completed faster, others slower, and others much slower than the time stated.
2) The average processing times assume that you pay the fees upfront. Not paying upfront can add up to 60 days to your processing, but it will not decrease the average times shown.
3) Both parts of the spousal application are submitted together.
4) There is no minimum income requirement to sponsor a spouse and minor children.
5) No.
6) You're in such a place right here in this forum. As for free in the UK or NS as in one on one, I doubt it.
7) Canadian immigration law requires that applications for permanent residence be done outside the country. Inland applicants have this requirement waived, but that waiver comes at a cost, including a longer processing time.

You MUST include any children you have, whether they will accompany you or not. Failure to include your children is a misrepresentation, and it also bars you from ever sponsoring them if this becomes necessary in the future.