H1B and spouse on F1-OPT

Hello,

I’m on H1B and my spouse was on F1-OPT last year.

1. If we file taxes to together and from what I understand she will be treated as being on H1B. Does that mean she will owe social security and Medicare tax? On F1-OPT she doesn’t need to pay that.

2. I have some capital gains, dividend and interest income. I also have some carry over losses from last year which I can offset this year.

3. We didn’t change our w4 and it’s showing single for both of us.

Looking at the situation does it make sense to file separately or does it make sense to file jointly? I’m assuming if we file jointly then she can file her taxes online with me.