How do you do in dense crowds? Do you expect to ride lots of rides? Are you claustrophobic? If you don't do well in heavy crowds and if claustrophobia is a problem, then NYE at DLR (in fact, the week between Christmas and NYE) probably isn't a great idea for you. If you want/expect to ride lots of rides without waiting in long lines or if you don't do well waiting in long lines (for everything: rides, food, restrooms, etc.), then another time of year would probably work better for your trip. NYE can be really fun at DLR, but you must have realistic expectations and know how well you do or don't do under crowded conditions. Some people love this time of year and make a NYE DLR trip an annual tradition. Other people try it once, hate it or are very frightened by the whole experience, and never do it again. Only you know which group is yours.