problem with writing to my storage disks

[John Pierre]

Ubuntu's great.  the only linux i feel at home with.  one problem
though- Ubuntu does not allow me to write (save) to my linux disks-which
i use for storage.  I tried everything, from trying to login on console
as root, and changing user permissions.  I also changed the etc fstab
file.  It allows me to read write to windows mounts, but denies me ext3
mounts.  entry in etc fstab: /dev/hdb8 /media/linstor ext3 defaults 0 0
i probably made a wrong entry. 
Help anyone?
Also how can i login on console as root to change user permissions.
Ubuntu made me root and also a user, and seems not to be able to
distinguish between the two.  / has root and Longi as users, but there
seems not to exist a root account.  I allowed root to login with GDM but
would'nt work.
John Pierre.