Moving to a new country is always difficult, especially when there is a cultural or language gap. However, the adjustment can be made more smoothly if this is anticipated and prepared for, so that you know what to expect. Our page on Culture Shock in Romania has some useful information to get you started.
As your children are still very young, they should be able to pick up the language quite easily. This would give you the option of sending them to a local public school once they are a bit older, which is a great way of integrating them into the local culture.
For some insight from other expats who have made the move, have a look at our Expat Experiences in Romania page. Two of the four interviews there are with American expats in Romania, so those two are probably a good source of comparison, although of course everyone's experience does differ to some degree.
As you and your husband have friends and family in Romania, the emotional support should help you to adjust.