This is something you can't take lightly, and you must understand the you are doing this at your own risk. You will also be effectively be voiding your warranty. Read everything several times if you wish to proceed. One you are sure read again.
First you have to do this....
http://www.atrixforums.com/forum/motorola-atrix-hacks/4414-how-root-motorola-atrix-1-all-versions-including-stock-locked-2-3-4-2-3-6-a.html#post47155
And then your have to do this...
http://www.atrixforums.com/forum/motorola-atrix-hacks/3331-tut-unlocking-bootloader-installing-custom-roms.html#post41669
Good luck.
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