Hello to everyone!

I heard so many good comments about Linux and they moved me to try it. I'm not really good in computers, just a regular program user. And because of my curiosity I decided to Install Linux Mint 13 Maya. But out of precaution I did it in my external Hard Drive. after following some steps found in the internet, now I just can get to load it in my computer. after trying to boot from the EHD there is this Error that comes out and I don't really know what to do.
it says:
error: unknown filesystem
Grubrescue>_

Could anyone pls help me to get out of this stumbling block which prevents me from finding out the beauty in Linux.

Thanks in advance! Ah pls try to be as explicit as possible because I'm really poor in all this thing of computers.

The simplest thing to do to get help would be to go to the site below, read the instructions, download and run the bootinfoscript and post the results.txt file here. The information you have provided is not enough for anyone to really help:

http://sourceforge.net/projects/bootinfoscript/