permissions

Changing permissions and owners is a good way to bork your system. In Linux there is a Root owner that is all powerful. You are not root and you shouldn't be. Being root all the time is a good way to bork your system too. However, you can become root temporarily. To do this you use sudo or gksudo (for gui apps). You will also be asked for your password when you install things. As the first user you have sudo rights and your user password is your sudo password. I don't use azureus so I don't know why it isn't updating properly (i.e. asking for your password). See https://help.ubuntu.com/community/RootSudo for more info.

PS do NOT chmod or chown your whole system.

   Thanks for answering Jim, but this still doesn't help me erase my USB drive. I did it by borrowing a windows computer (oh! the shame). I would like to be able to do it myself. As for the Azureus thing, I guess the only other thing is to change bittorrent clients.
       Thanks, Ian

Please insert your usb pen and please open a Terminal from the menu Applications->Accessories->Terminal and type:

sudo fdisk -l

give your user password when requested, you don't see nothing when you type it, then press enter.

Copy and paste result here.

Thank you

 Hi Marcoba I'm confused, what is the character at the end of statement.
         Ian

Ian, it's a small letter L. It will output the device names and characteristics for the various drives including any USB drives connected.

Thanks again Jim,
 Here is the information you asked for Marcoba.
Disk /dev/sda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x33f233f1

   Device Boot Start End Blocks Id System
/dev/sda1 * 1 19269 154778211 83 Linux
/dev/sda2 19270 19457 1510110 5 Extended
/dev/sda5 19270 19457 1510078+ 82 Linux swap / Solaris

Disk /dev/sdb: 40.0 GB, 40020664320 bytes
255 heads, 63 sectors/track, 4865 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x34243423

   Device Boot Start End Blocks Id System
/dev/sdb1 1 4864 39070048+ 7 HPFS/NTFS

Disk /dev/sdc: 1014 MB, 1014497280 bytes
65 heads, 32 sectors/track, 952 cylinders
Units = cylinders of 2080 * 512 = 1064960 bytes
Disk identifier: 0xc3072e18

   Device Boot Start End Blocks Id System
/dev/sdc1 * 1 953 990704 6 FAT16
Partition 1 has different physical/logical endings:
     phys=(967, 64, 32) logical=(952, 39, 32)

   Hope this helps
 Ian

Thanks Jim Hutchinson, that solved my question.

 Thanks Jim, I used my mates windows computer again ( I'll never live it down) That fixed it.

Well, just remind him that it was windows that broke it so naturally windows should have to fix it. It's only fair. Glad I could help.