stuck at loading screen?

[Quicksilvr]

Hey guys, i'm new to linux and i'm using ubuntu 9. For some weird reason, sometimes when i log in only the ubuntu logo shows up. It says "Grub loading" and then the logo appears, but the harddrive isn't accessed. After about 2 minutes, the logo disappears and the screen goes blank. I have to shut down the computer manually.

The weird thing is, it only happens every so often..about every other boot up. Can anyone tell me how to fix this?

[quixote]

For some reason, the system sometimes isn't finding the files it needs on bootup, which might be a bad sign (failing hard drive??) or might be something fixable. I don't know how to fix this, but if nobody's answered your question in over a day, it's okay to "reply" to yourself so it gets bumped back up into current questions. So that's all I'm doing here :) . Hopefully, this time, somebody will see it who knows.