Again, it's your call. If you are one of those people that likes to do a clean install of the OS regulary, then I suggest you make a smaller partition for the OS and a larger partition for data. this way you can blow away your OS partition and reinstall without effecting your data (movies, pictures, documents,...). Of course, repartitioning now will require a reinstall of the OS or a partition manager that can alter the partition table without destroying any of your data (not always full proof). In either case, I recommend you make backups since anytime you mess with the partition tables you risk loss of data.