Ha, I did the same thing when I bought mine. I tried to re-charge the battery and it started strong for a few days, then a sudden no start situation again.
You don't really know the state of the battery and this car is very temperamental under less than ideal battery conditions.
Just get a brandy new battery. It's worth the peace of mind.

 

Glad to see the chap sorted and he can enjoy the ride . on nites call out its a bummer we all got to take our turn

 

My car will not start and I had to find a way to get it into neutral so that it could be towed. There is a video of how to do this on Youtube. There is a mechanical lever under the rear shifter that you have to use a long flathead screwdriver to push it and at the same time pull the gear shifter down into neutral. I hope that this helps.
Here is that link:

 

Akazper75, the XK/XKR does not have the same shifter as your X-Type. Also, there is no way to get one out or park without battery power.

 

Yes, there is a screw under the console hole that can be removed and a rod shifted to release the park to enable towing on the XK.

 

On the 5.0L cars, not the 4.2L.

 

4.2 is easier, pry the latch with a screwdriver.