Sight: Without sight then I can't play video games, read, or look at attractive people. I will not give it up.
Hearing: Without hearing, I can't listen to the world or people and it'd be easier for someone to make fun of me behind my back. Also, I'd have to have subtitles on EVERYTHING! I will not give it up.
Smell: I see this is the majority voted for. But those people don't realize that without smell, your subconscious can't smell pheromones and therefore you'd have little to no sex drive. Just a little tip

I will not give it up.
Touch: Well again, no sex drive. And also, pain is good for warning you of stuff. The people without nerves, and no pain, often die sooner or are permanently injured by stuff. I will not give it up.
Taste: So what, without taste I can't taste food... that's it. I can still make delicious food that other people can compliment me on. And I'd be able to eat anything that I didn't like because, hell, I couldn't taste it. Goodbye taste.