1.By checking the specifications of mb, how can I assess what hdd options I have?
You can use upto two IDE HDD, and up to 6 sata dvices, like DVD/CD, HDD, SSD.
2. What are the high capacity, fast access 1 TB and more, hdd options do I have?
you can use up to 2TB hard drive without any problem, if you use 3TB or up and depends on the OS too, you need to format the hard drive to GPT format. https://en.wikipedia.org/wiki/GUID_Partition_Table
3. internal wifi options?
either add on pcie wifi card or USB wifi.