congratulations bil_drk, you have found CMOS
Yes, it looks like DOS..
Now, once you are in CMOS setup, use the arrow keys on your keyboard to navigate around, generally, pushing the left and right arrow keys allow you to navigate to the different available categories.... and the UP/DOWN arrow keys let you select what you want to do in each sub-category... Look in each category and look for something that resembes, Start Order, Boot Order, Drive Order, Start Sequence, or Boot Sequence.....something along those lines....catch my drift? Once you have found that let me know and I'll guide you through changing the order of the drives..