The problem is that a solicitor would need more information from you than you have provided so far. You have mentioned nothing about such matters as income and pensions. But if you split up, these would be important considerations. I can safely say that a Court's first priority would be the welfare of the children ( both yours and hers ) and that means, primarily, that they need a roof over their head. Normally what happens is that the divorcing couple have children and they are the parents, and the parent who has the day to day care of the children will be in an advantageous position when it comes to the
marital home. But here you are both parents and one assumes that if you split, the children will go with their parents, so they both need a home.
The second difficulty is that, when it comes to short marriages and inheritances, the law is very unclear. Your wife has actually inherited the money, so it forms part of the ' pot ' available for distribution. The fact that your wife inherited it would undoubtedly be a factor but I think a Court may think it is less important than the childrens' need for a home. Furthermore, your respective ability to borrow and raise a mortgage could be important too.
Your wife is not necessarily correct in assuming that, because the house was primarily bought with her money, she must get the lion's share of the equity. The reason is that the childrens' needs will be paramount. The other point is that, the longer the marriage, the less it matters that your wife inherited the money, as it would become subsumed in the general family finances.
The answer to your question is yes, it is worth taking legal advice, but do remember that divorce almost always means a reduction in living standards for both of you. I can understand why your wife feels the way she does, but you originally saved her bacon by inviting her in to your home in the first place. It seems to me that a little bit of counselling might help the two of you to work better together - you seem to me to have a reasonable standard of living and I don't want to push you into divorce if there is a reasonable chance of saving your marriage. Sorry if I get in my tuppence worth, but it's worth thinking about.
Mike