Greetings,
You’ve already answered your own question. The word “HADES” (hell) here is metaphorical. It doesn’t denote the grave, but a deplorable condition or state.
The Bible uses Sheol/Hades as a very common symbol. It is regularly used in the Scriptures as a symbol of a despicable state. Several times David thanked God for delivering him from HADES (Ps.30:3; 86:13, LXX). When Jonah was in the belly of the fish he said he was in HADES. Was David or Jonah literally in HADES? No. But they were in a despicable condition and wanted to be released. Likewise, in parabolic language "HADES" here in Luke is not literally the place where dead souls are. It is the figurative Sheol/Hades as used by David, Jonah and many others.
Many Bible scholars recognize this figurative use HADES:
S.T. Bloomfield in his Notes on the N.T. says HADES is a "hyperbolical expression, figuratively representing the depth of adversity."
Adam Clarke: "The word 'hell', used in the common translation, conveys now an improper meaning of the original word;...Here it means a state of the utmost woe, and ruin, and desolation."
A parallel usage of HADES is in Lk 10:15 (Mt. 11:23). "And thou, Capernaum, which art exalted unto heaven, shalt be brought down to hell" (hades). No one would contend that the city of Capernaum was literally in heaven, nor was it to be literally sent to hell. The word hell here is a figure of a "state of utmost woe, and ruin, and desolation" as a result of God's rejection.
Interpreting this account to be speaking about the literal grave would rip the parable out of it's context, which is not teaching anything about what happens after death. Rather, it is clearly an illustration depicting the difference in the *spiritual* conditions of the "rich" Pharisees and the "poor" common people (Lk.15:1,2; 16:1,14). This is easy to see since the context is in response to scoffing by the Pharisees, who were "money lovers" and setting themselves in an exalted position (16:14,15). Yet, the common people "kept drawing near to him to hear him" (Lk. 15:1,2).
So the parable depicts a change of circumstances from God's standpoint. The Rich man represented the Jewish religious leaders, who were favored with spiritual privileges and opportunities, whereas Lazarus represented the common people to whom the religious leaders denied spiritual food.
The rich man dwelling in Hades represents the spiritual degradation now experienced by the Pharisees. They now "thirst" for even a drop of the spiritual waters they had previously (Am.8:11). The fiery torment experienced by the rich man represented Jesus' messages of fiery judgment proclaimed by Jesus' disciples that tormented these religious leaders day and night (Acts 4:1,2; 5:17, 18; 7:54).
Yours,
BAR-ANERGES
EDIT:
Actually, what it means to be "buried" and "carried away by angels" is implied in the answer. Being "buried" is simply part of the change from a favored state to a despicable state and likewise being taken by angels is part of the change from a despicable state to a favored state. The care of Angels is a figure of God's favor.
But you also need to be careful of trying to force some significance into each and every detail of a parable. One exegetical rule is that every parable must have some details which have no real significance outside of supporting the primary point. This was the mistake of the bizarre interpretations of many early exegetes; they wanted every little detail to have some meaning.
One edition of the NAB states: "Parable: A short fictitious narrative from which a moral or spiritual truth is drawn. Keep in mind that the point of the parable (not the details) is God's message to believers."
"Contrary to an allegory like Pilgrim's Progress, where every detail counts, the details of a parable do not necessarily have any significance in themselves, except as "props" for the story. A parable is designed to teach a fundamental truth, and the details do not have a literal meaning, unless the context indicates otherwise. Out of this principle another grows, namely, only the fundamental teaching of a parable, confirmed by the general tenor of Scripture, may be legitimately used for defining doctrine."--Samuele Bacchiocchi; The State of the Dead
"A parable is a truth carried in a vehicle. Therefore there is the inevitable presence of accessories which are necessary for the drapery of the parable, but are not part of the meaning. The danger in parabolic teaching at this point is to interpret as meaningful what is drapery."—Bernard Ramm; Protestant Biblical Interpretation