I wouldn't cut anything back without knowing exactly what type of Hydrangea you have. Being that you got no flowers last year makes me think you have a macrophylla. Mulching would probably be a good idea, especially if it is a macrophylla.

I agree with above poster - don't cut back until you know what you are dealing with.

A couple things can clue you in in you saw any flowers on the bush in the past:
* Are the flowers bluish or pinkish? If so, is probably a macrophylla, blooms on old wood, so do not cut back, and good idea to winter protect. May be an Endless Summer, which blooms on old and new wood, but wouldn't be able to tell at this point in the season. If flowers are rounded white, may be either a macrophylla or an Annabelle-type, would advise not cutting back and winter protecting until you can determine.

* Are the flowers kind of flat and turtle-shaped? If so, you have a lacecap - again, don't cut back, and winter protect.

* Are the flowers conical in shape? If so, you have a paniculata-type, which blooms on new wood, so cut back in the spring (trim to shape, not a full cut-back), no winter protection necessary.

* Keep an eye on them next year and note if the flowers are coming off of new wood (new branches) or old wood/branches - that will tell you what you're dealing with.

As far as winter protection goes, if you do a forum search, there are a multitude of posts regarding this.

I hear ya, I got my place in '07 and cut back all the old growth on all but three stalks. Well the next season only light blue flowers on the three stalks rest bare. problem now is the plant put some much energy in new growth it got HUGE and is crowing other shrubs! Should I just cut back the over reaching stalks leaving the rest behind.