Two hard drives needn't mean a RAID array - it may just be two drives. If you can tell us what the motherboard is, we can probably tell you if it's set up as RAID. I would think it very very unlikely (maybe impossible) with two drives of such low capacity, and different capacities. - this probably means an older computer. I would think the second drive has been added simply for more storage space.
The drive with the Master jumper will be the Master (surprisingly) - and the one set to Cable Select will be the Slave. Cable Select drives become Slaves when fitted to the connector in the middle of the cable. Although these jumper settings are odd, they are quite acceptable and will work OK.
Windows will automatically install on the Master drive. Put in the CD - set the system to boot from the CD and follow the instructions on the screen. You should repartition the drives (set only the one partition on the Master - the Slave you can do later), and Format it to make sure it's clean and in good condition.