If the woodchip paper has been on a few years, when you take it off, it will probably damage the plaster!! So the best option is to re-plaster the whole room as you would have to repair all the walls before wallpapering anyway! Once plastered, then you have the option, to either paint or wallpaper.
I would suggest painting it, then it’s easier to paint in the future, if you change your mind about colours.

The best way to check is to simply tap your knuckle along the wall(s) in question. If they are "blown" (builders term for the plaster no longer being stuck to the wall) you will know by the sound. If it doesn't sound solid, it isn't.. From my experience, Woodchip is normally there when walls are not in a good way. If they don't sound hollow you are best off stripping the paper (with a scraper, not a steamer as this could cause more problems) filling and painting. For the perfect finish, plastering is obviously the best option. It all depends on your budget and the finish you want to achieve.

Plastererers will say plaster it( for obvious reasons lol)
Once you've grafted the removal of woodchip you might find the walls not too bad. Some filling and prep and you could re-paper with a blown vinyl then paint. A job easily in the scope of a diy'er