Problem with first thing to do.

Hi. Im newly involve with beagleboard xm with a week linux experience. My objective is to run .cpp code file with opencv library in beagleboard xm. I googling around and wandering at this community forum, blogs and I found that several tutorials quite useful but I face a lot of problems and dont understand majority of the instruction or topic discussed since i still a newbies. I thought maybe any experts can give a hint or guide me for this embedded journey. My questions are: 1. I burn an angstrom image from for my beagleboard xm. Is it the most efficient os that i can use? or the kernel? 2.I also tried ubuntu 14.04 ( and it stuck after i update, upgrade, and try to boot into a gui environment. I refer to and for boot up and gui process. 3. Once i burn an angstrom image and boot beagleboard xm up, i read view blogs that advise to update and upgrade right after the first boot. So i tried to “opkg update” and “opkg upgrade” but it stuck at login screen after complete upgrade and reboot. What should i do? What the first thing i suppose to do after succesfully burn and boot? 4. When i gave up with update and upgrade, I just proceed and followed this tutorial here and it work until v2l-utils command. And i believe i need to install video4linux first. And how should i do it? Anyone could recommend me some links or books that i can refer as a newbie in linux on beagleboard xm. Thank you a bunch.