If I include a table in a form can I include, at the bottom of a column, a total of all the values in that colum?

Likewise, can I perform calculations across columns (along rows), for example Qty * Value to appear in last filed of a row?

Based on what you have mentioned, I presume that you will be using some widget such as Spreadsheet widget which would allow calculation or some other?

If you could give us the link to your jotform and let us know which tool/widget you would like to have this set on we would be happy to check and offer you with samples on how to do it or offer alternative options (like the Spreadsheet widget above, if that is not what you already had in mind).