I've always found the coopers yeast to be very reliable and tolerant of quite a range of temperatures within reason. So unless you have a strong desire to use a different yeast I would run with the one supplied.
Regarding the hops. The easiest way to use them would be as a dry hop. Quantities are a personal taste. I used to use between 50 and 100g of leaf citra as a dry hop with reasonably good results. You could also consider boiling a quantity of the kit and adding some of the hops at the end of the boil or with 5 mins to go. The options are endless......
Which ever option you go for I would write it down so you can replicate it or tweak it next time.
PS the Canadian Blonde kits are worth a go as well.