folding flopped non nut full house in an unraised pot?

[greywolf]

ok so im small blind in ladbrokes 10/20$ game 10 seater, had just sat down. i got 2,4k and main opp has about the same. I have played with this player before shes a decent TAG but thats about all i know about her.
A couple of people limp and i put in the extra 10$ with 246T ds it isnt much i know but it was cheap. So the flop comes down 224 ( two spades) and i bet out the pot which is 100$ and i get raised to 400$. What do i put her on? 2AAx ? 24xx with two spades, 24 with a pair in her hand, or the nuts?
Whats your move here? I made what could be the worst possible move i min raised to 300 more then folded when she instantly pushed allin..That really bugs me..i amlost never min raise or bet anything less than the pot since i think thats often a weak move. Here i got some weird idea in my head that it would be great move...
Anyway I got real scared when she played this so fast, not really quite her style. Am i too scared here fearing the nuts? Does she make this play often enough with say 2AA4 to make it +EV committing all my money on the flop? Is her way of playing this hand so fast perhaps a sign of weakness i.e a pair in her hand reducsing her redraw outs, or a sign that shes got the nuts?