In the opening stanza, of the poem the speaker stands in the woods, at a fork in the path. He stands for a long time trying to decide which of the two paths to take, wishing that he could travel down both. The fact that the speaker admits to being "sorry" that he can "not travel both" roads suggests that he is wistfully longing to explore both. Perhaps the roads here metaphorically represent different life choices that the speaker is faced with, and the speaker's longing to travel down both roads indicates his regret that he can not live every potential life available to him.
The speaker's state of mind in the opening stanza is also indecisive. He describes standing for a "long time" at the fork in the road, indicating that for a long time he is unable to decide which road to take. The implication is that he regrets that making a decision to travel down one road rather than the other must necessarily preclude him from knowing where the other road leads.
The speaker's state of mind in the opening stanza might also be described as curious. Indeed he looks down one of the roads "as far" as he can to try to determine where the road leads. The road, however, bends into "the undergrowth," preventing the speaker from satisfying his curiosity.