Braided lines will improve pedal feel. I like to use Raybestos rotors and have always had very good performance from them. Get them from Rockauto or Amazon. For pads I use Centric Posi Quiet. Zero dust and they stop great.
After you do the lines and do the pads/rotors do a full power bleed on the whole system and you should be good.
Since you already have a Cobra, you have pretty good brakes already but if you wanted to upgrade past this prepare to spend $1500-$2k.
2000 Mustang GT Steeda build #48. Bolt ons, suspension, Novi 2000.
Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.