Yes they should be. i would recommend going for atleast 500GB HDD.
Found a HDD that costs ~50% more but comes with 400% more space for storage. i putted it in this list:http://uk.pcpartpicker.com/p/3oSIn
Windows 7/8 (if you install that) will take up ~30GB alone, for these extra £10, you'll feel like your pc has infinite storage compared to 250GB, it should also be faster at loading.