no problem in rooting... below is the step:
-just download the z4root.1.3.0 and install it....
- after install, restart your phone (yes....shut down and power on back....)
-plug ur usb cable to ur phone & connect to pc.
- make sure u turn on the USB DEBUGGING (u can turn on from > setting>application>development)
-don't enable the USB disk drive.
then now open ur just installed z4root program, choose the permanent root... (dont worry, u can unroot anytime with the same program!!)
it will run by its own and within a miniute ur phone is rooted!!!

by the way, you should root 1st, then backup all your preinstalled program using the titanium backup, use mybackup to backup ur contacts, sms/mms. pls copy down ur APN setting! (just in case u forgot how to set when u change to other rom!!
the tricky part is to install the custom recovery into the O1....
u may refer to
http://www.tech-mania.com/2011/installing-...om-recovery-lg/sound ez for rooting the phone..n hard for custom recovery...btw...wad is the purpose for rooting?got more benefit?can b like high-end phone?hmm..after done custom recovery..whats next?