Hi Lily, nice to see you getting your hands dirty!!
You don't need to change the front sprocket just because you change the rear, but for the sake of 7 quid you may as well!
If you want to stay standard you need a 94 link 520 O' ring chain plus the 36 tooth rear sprocket.
Personally I would highly recommend changing to a renthal or similar sprocket carrier, as, although the initial purchase is dear, it is cheaper in the long run, and you can chage your rear sprocket in a matter of minutes.
I would recommend a 96 link chain and a 39 tooth rear sprocket, it goes like a rocket and you can go up to42/43 without having to lenghthen the chain.
Try Terry@Redtec for a second hand carrier and sprockets, I got mine from him for £100 for a carrier and two sprockets, his number is 07974925835, and tell him I sent ya!! :P
If you have any woes, give us a shout
