1. If it's IDE, the SSD has no bearing on the IDE HDD. Set the HDD appropriately for the IDE bus (e.g., if it's the only IDE drive, set it to master, if there's another drive on the IDE bus, then set it appropriately; whatever the other drive isn't).
2. You don't need to format the HDD to allow access, but if you don't need the data on that drive, I'd suggest doing it. Just keeps things clean, wipes the other boot record. Just advising for cleanliness. But you can access your data without doing that.