It is perfectly fine and normal for you to appoint your Son as sole Executor and leave everything to him.
It is perfectly fine for you to say that "I leave all my Estate to my Son xxxx".
It would also be wise for you to appoint substitutional Executors in the unlikely event that your Son dies before you, as well as stipulating that if anything happens to your Son, then the Estate should pass to his children on reaching the age of 18 or 21 (although I appreciate he may not have any children at this stage). Alternatively, there is nothing stopping you from doing a new Will in the future if circumstances change.
I hope this answers your question and sets out the legal position.
If so, please don't forget to rate my answer.
Hi, without seeing the documents I can't really say, but if each of the sheets say much the same thing, other than the exact wording as to who gets the Estate, I would suggest you use Form 2.