For me Oblivion is a guilty shame
At the start of the game you are given the ability to choose different races each with their own unique skill set. You can also tweak the way your guy looks. After you select you character you are launched on a training mission where you travel through an old prison on the heels of an escaping royal party having just suffered through a botched assassination attempt. At the end of the mission you are started on you main quest and dumped into the game's massive world. However, what you do at this point is up to you. You can go on the main mission or the side ones. If your not up to taking orders from complete strangers, you could also wonder around; building skills by doing things over and over. . . and over. That's one the games only major faults jumping up and down and casting the same spell over and over seems to me more like work than play. But often times running around to build skills causes you to discover the millions of nuggets hidden in the game so the effort can be rewarding in more ways than one. Character interaction is the game's only other major drawback. There are only a handful of voice actors and hundreds of NPC's. After a while of playing you can get a sense of Dejavu.
All-in-all the games huge world, variety of ways to play and nice graphics make this a great game for people new to the RPG genre and experienced players alike.