Need help with my netbook!?

So, I deleted something from my netbook to make it faster,now the whole thing is messed up! My system is not running because of that.I cant get on the internet:L Then I got all the books and leaflets I got when I bought it and the disk said it 'restores applications and drivers if they do not run proper' but I have a netbook so where am I supposed to put it?Really need help:(