Tim of Gothridge Manor has some interesting comments on why he bought a Red Box Set. He is gaming with his wife, Ivy, and they just tried Swords & Wizardry. While it is simple to learn, characters die rather easily at first level. To newer gamers trying learn older editions this may be frustrating while learning the game.
D&D 4th edition in contrast beefs up hit points and has more options for a 1st level character to do things in combat. It is smoke and mirrors as the monsters likewise are beefed up and a 1st level characters will die just as horribly. But it will take longer, and the players will feel they have done more things before dying.
If I ran into a novice player or novice players that are not having a good time starting with 1st level with older editions, I would be to start off at 3rd or 5th level. The options are still manageable and you are a lot more survivable. I would also do this for a campaign that is esstentially solo play with a referee that has a single player.
I also recommend the XP charts found in Jeff Rient's Tower of Xylartarn. I use these for new players coming into the Gold Star Anime game in Edinboro. I also like how they take into account the prime requisite bonuses.
In the end the RPGs we used are tools to play a fun and exciting campaign. These are just are few more options.