Stand alone ssd or both ssd and hdd

Just wondering if its a better idea to buy a larger SSD (256) or a smaller SSD and a HDD, and just to clarify I don't need a lot of storage space so 256 is enough for me.

If 256GB is good enough for you, then just go for the single SSD. No point in getting a large hard drive and a smaller SSD if you don't need the extra space.