Be careful with the Red Box. If it is the dungeon I'm thinking of, then it is certainly capable of TPKing a level 1 party if someone sneezes at the wrong time, or if you split it across multiple sessions and someone isn't there for the whole thing.
Experienced players will probably steam-roll it.... but as newbs they might find themselves in the position of being hit 50% of the time for 8-9 points of damage, and only second-wind-ing for 7... which can seem like bad odds.
If I was doing that dungeon again with a level 1 party, I'd want:
(a) everyone to crank up their defences (17 is too low)
(b) much more aggressive use of action points for second-winds.
(c) I'd want a leader specialised in healing (e.g. both their encounter and daily powers as healing powers: for a Warlord this means something like Bastion of Defense and Myrmidon Formation. Yes I know this is 'suboptimal', but if the more 'optimal' choices result in party-wipe, then who is the bigger fool? Healing Strike + Beacon of hope for a Cleric perhaps.)
(d) Additionally, I'd want at least one, possibly two or more characters built around 'regen' by which I mean those builds which when they hit with X they get temporary hit points, and when they have temporary hit points they receive Y benefit.
(e) And lastly if there's a Cleric tossing around Sacred flame to give people a little bit of additional 'healing' (or someone else using a similar at-will) then all the better.
It's too much to ask really, but I'd also want my dice to not hate me! ;-)
On the other hand, it could be worse... it could be 3.5 :D I recently played a couple of different low level clerics, and managed to squeeze about 30 points of healing out of about a dozen cure light wounds. Great.. I rolled a 1. You get two hit points back. Again. **FACEPALM**