I did this post last year but forgot to publish.
We had the misfortune to learn that our toilet hadn't been properly installed by the prior owners of our house. This was by way of smelling rot coming up from the floor - an investigation turned up the below first picture - sodden wood overly that had been quietly fermenting like a good beer should under the lino.
I ripped the lino off, then a layer of wood which had been placed over the original lino .... and then I removed a million nails and the old think black glue that had been used to make the original lino stick to the floor boards.
Then I let the floor boards dry out for several months. Luckily none needed replacing (unlike the bathroom which is a whole other story...). A quick sand followed by a stain and then a coating of polyurethane and the job was done.
I quite like the final look - it's pretty rough and looks darker in this picture than it really is but the effect is quite cool. Not seen in this above picture is I also did a paint job on the skirting board and then sealed it off with some good old transparent Selly's.