I've had all sorts of things for Christmas which haven't been my taste or of use to me (and no doubt some of the presents I've given will have been viewed the same). However I rarely throw them out, they go to the charity shops instead, and in turn I've bought all sorts of things from charity shops, possibly unused gifts, which I've loved, so somewhere in the circle, we've all benefitted.
So, to answer the thread, my worst presents were a tin of chocolates from an aunt, 4 years beyond the use-by date (I did bin those), and an iron from my husband. We were short of money and the old iron had packed up, but he knew I hate ironing and avoid it at all costs, so I was pretty hurt at that.
However, best presents were, a beautiful collage of old black & white family photos, put together by my sister with a brief family timeline in calligraphy down the side and beautifully framed, for Christmas last year, and the first motorbike I had, bought for me for my 50th birthday by my husband, and which has led to years of pleasure, even though I later moved on to a bigger bike.