Yes, ditch the tables and use columns/spans with an <h> tag instead of a table heading.
What you've got there is way beyond typical table content.

*You might want to consider a responsive grid before you get too far along with a static site.

What would you suggest regards columns and spans, could you point me in the right direction?

Would it be difficult to convert this structure to responsive? It was a pre-purchased template.

There are many responsive grid/frameworks available. Coffee Cup recently added their own product, Responsive Layout Maker Pro. It makes it easy to build your layout either with their own Coffeegrinder system or Bootstrap framework (others will be added (maybe Foundation will be next?).
Grab a free trial and have a go with one of the included layouts.

With Google sending out notices to site owners that their non mobile friendly sites will suffer in search results, a static site is just a waste of your time.

Iwill need tolook into how I can convert the present layout into a responsive one.