Hi and welcome to SevenForums,
cd/ dvd drive is usually first but I don't believe it makes a difference as long as the os is next in line
To make windows the default you do that I believe via Linux boot manager or grub not sure the correct naming of the screen but that is where you make Linux or windows the default os.
My Computer
At a glance
Win-7-Pro64bit 7-H-Prem-64biti7-5930K 2nd i9-9940x both water blocked VRM'...Trident-z 3200C14 2nd Trident-z 3600C16EVGA 1080ti ftw3 2nd Titan Xp both water blocked
Computer type
PC/Desktop
Computer Manufacturer/Model Number
Custom assembled by me :}
OS
Win-7-Pro64bit 7-H-Prem-64bit
CPU
i7-5930K 2nd i9-9940x both water blocked VRM's too
2nd ASUS X299 Apex/Intel i9-9940x with Custom water loop/7H-Prem-x64/Corsair 450D case/Ram Trident-z 3600C16 4x8gb / Samsung970Evo plus 500gb SSD/Dual ssd EZ swap evo/PSU EVGA SuperNova 1200w-P2 80+Platinum/GPU Titan Xp /8-ML-140 on push-pull on 2-280GTX rads