I am exploring moving to the UK after 45 years in the US, my question is my US wife would use her 401K as her savings route but could I use that too even if its under her name only, there is enough to cover both of us.
Yes, that's fine. The savings used can be either held in an account your name, in her name or in both your names jointly. Remember, the savings are only required to show you have enough to support HER, not you... because as a UK citizen (I assume you are a UK citizen?), you are legally allowed to claim UK benefits to support yourself.
However, she would need to make sure that the funds are immediately accessible and can be withdrawn at any time, either with or without penalty. She would need to provide proof of this in writing from her 401K provider.
We could sell our home and use the profit but that would require selling prior to applying. I am a stay at home parent so therefore do not work currently.
That can also be done, and as long as the house was owned by you at the beginning of the 6 months prior to applying, you wouldn't need to hold the proceeds from the sale in your accounts for 6 months before applying... though as you said, it does mean having to sell before you apply for the visa, which is not ideal.
Just a tip: it's best to post your questions about meeting the visa requirements in the 'Visas and Immigration' section of the forum, because the Expat Life section is for people to discuss life in the UK after moving here, and if your visa questions are posted in this section, they might get missed.
