@futonrevelation, if you're inexperienced with the terminal, I would suggest you don't use it to do sensitive stuff, that might result in losing your wallet file. You should use the graphical interface.
Since you said you're using Ubuntu 11.04, I suppose you're using the Unity interface (the one with the square buttons on the left side of the screen) ? If so, open your home folder, it looks like a folder with a home on it
![Cheesy](https://bitcointalk.org/Smileys/default/cheesy.gif)
. Go to View > Show hidden files (or press CTRL-H) and you should see a bunch more folders than before, a lot of them starting with a dot. These are hidden files, and ".bitcoin" will be there too. Open it and copy and paste wallet.dat to another folder (your Desktop, for example, or a USB stick, which is a better idea. You should do this simple backup every week at least, if not every day). You can then delete the corrupt files and reload the client.
Good luck!