Played the first few hands of the tourney and won one pot, then my internet connection went out for about 20 minutes, then it came back on when the blinds were 50/100 so I have no reads on these people, so push or fold?

Party Poker No-Limit Hold'em Tourney, Big Blind is t150 (6 handed) internettexasholdem.com

MP (t1625)
CO (t480)
Button (t1560)
Hero (t930)
BB (t1675)
UTG (t1730)

Preflop: Hero is SB with A[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/club.gif[/img].
<font color="#666666">CO goes all in for 480, folds to hero in sb</font>. Hero does ?