Wolfspire
So ReddTarga if the speed rating which is H is higher that should be ok? if im wrong please do correct me!

Yes, and it is probably the sort of thing that would be checked if you were getting a roadworthy.
But if you want to learn more about tire speed ratings, Google is your friend.

I went through the tyre size exercise two years ago, upgrading from the standard 14" wheels. 17s are the first size that now really has performance tyres, and the Kumho I got were one of the few that that you could get in both the front and rear sizes. 
The 215/40/17 work quite well. The rear 235/40/17 is needed for the load rating. With either 225/45/17 or 245/35/17 there isn't enough air inside the tyre to get the load rating without going to XL tyres (stiffer sidewalls and heavier).
From memory the diameter rule was something like no more than 15 mm and then 3%. With 235/40/17 compared to 205/60/14 you need the 3% bit to stay within the legal maximum diameter. The speedo will run low. 
A wheel offset of +38 mm has been recommended. My new MCA coilovers have allowed a bit more clearance under the guards with my +38 front and +36 mm rear wheels.