I don't get the hate on the last 2 episodes. You people are taking things too far. It's simply Shinji finding himself after the crap-ton of trauma he experienced battling the Angels.
To clear up any confusion about the movies, here's an explanation:
- Death and Rebirth contains two parts - Death and Rebirth (duh).
- Death is simply a bunch of cut-out scenes edited together (which can also be found on the Director Cut versions of the DVD).
- Rebirth is simply the first half of The End of Evangelion.
- The End of Evangelion replaces the final two original episodes with it's own two episodes (the first episode found at the "Rebirth" part of D&R)
Watching the End of Evangelion really made me appreciate the original last two episodes. In the End of Evangelion, Shinji is still going through all of this mental stress and trauma - something that was fixed through inner-reflection in the original ending. Which of the two endings you pick is up to you.