Help with free shipping

[spuk]

Hi all,
I'm hoping someone here can point me in the right direction.

I've set up Royal Mail and weight based shipping extensions (for courier deliveries) which seem to work.
However, I have some products that I want to offer with free delivery.
If I select 'Free Delivery' in the product details, it shows all delivery options within that weight range for free at checkout.
In short, is there a way for either:

• Only free shipping option to be shown (unless other non-free delivery items in basket)
• All shipping options shown (but at their standard rates)

I had a look at the Free Shipping extension, but as far as I can tell, that's more for 'free delivery on orders over x amount' settings.

Any ideas anyone?

[maxter]

My understanding that you want to show only free delivery option (preselected) if all products in the cart have free delivery options.

There is a way to set default selected delivery option (auto select), but there is no way to disable other shipments. 

I have seen cases, where free shipment is a basic and other paid shipping options are expedited.