snags ...
This is more what I had in mind:
http://www.xrv.org.uk..._Harley_Davidson1.jpg
WILL ... great that your wife is in the clear. I hope they give her periodical scans so that they can spot it early if any cells reappear.
The best advice has to be to use the money wisely (of course).
But hey ... if your mortgage is small, and you can comfortably keep paying it, then why not enjoy yourselves?
But how would you present such a holiday? Not on the basis that you are making the most of it while your wife is still able to enjoy it. Thankfully, it sounds like that is not necessary, and your wife has been "cured" (subject to maybe needing bits of treatment to keep on top of it in the future).
Instead, think of it as a celebration. You must have been through a worrying time together, but things have worked out well ... so, go celebrate !