BB almost all in

[AriesRam]

Paradise 10+1. Blinds are 250/500. There are 5 of us left. I am in commanding lead with about T5000 after I post the SB of 250. The big blind has roughly T250 after posting his BB.

It is folded around to me, but I have 42o. Is it horrible to fold here? I figured he would have to call with anything, so I wouldn't be able to get him to fold. I also can't believe 42o would win 40% of the time agaisnt any two random cards. Was I right to fold?