Simply pull off the screwdriver attatchment and under is the socket drive

The screwdriver bit holder is infact a 1/2" square drive adapter - if you take that off you will see the 1/2" square bit.

take the silver adapter of the end hey presto ! a half inch socket drive

The end adaptor is removeable to reveal the half inch drive.

Pull off the bit holder to reveal a 1/2" drive

Yes you can but a breaker bar is less risky if you have alloys

By standard brace I assume you mean the less than 300mm one usually supplied with the screw jack in the car?
If this is the case first step would be to try an extending wheel wrench, if this fails then possibly try using the impact wrench. Best bet would be to take it back to where your tyres were fitted or last service carried out and get them to loosen them off as they were done up too tight.
However if you have Alloy Wheels and your fixings have been done up too tight there maybe some damage.

The best bet would probably be a proper air powered impact wrench, but as they're rather expensive, you could definetely try using this with a large hammer!

no get a extending wheel brace

Yes - no problem

You hit it hard with a hammer, only electric or air impact drivers are powered. The only limit is how hard you can hit it.

Powered by good old arm-weilding-a-hammer power

This is powered by using a hammer on the back of it - I guess the max torque is how hard you can hit it!

hit it with a hammer as it compesses it turns