Legitimate hands?

[stragf]

I realize this is vague, but I would like some thoughts. In a $50 freezeout, 70 entrants, and a medium environment (neither exceptionally loose or tight) what would your cut-off point of the 169 starting hands be, from all positions on average? 50%, 40%. etc??
After the flop, what would you consider to be (what Slansky calls) a "legitimate hand". In spite of doing well at these tourneys (in the money 30%)I believe I waste alot of bets at early and midpoint of the tourney with mid pairs (55-TT), solid suited connectors, where I miss the flop. I may end up looking at an overcard, a backdoor flush, three straight,and I check or fold when bet into, rather than taking the turn and the river, where I could draw something. It realize that position is important, but I started to wonder if people have a "minimum hand" that they would require before playing. (BTW, Has anyone looked at SLansky's "System" for Tournaments? Thoughts?)