"Names"

Frodo
The name is based on the old English word fród, which means "wise by experience". This fits our hobbit a lot, judging how much he lived through and how many things - bad and good - he saw.

Samwise
It was derived from the ancient English samwís, meaning "half-wise" or "simple". Sam definitely is rather straightforward and uncomplicated - Tolkien wanted to point out his servant role, but I don't think he is not wise.

Peregrin
Short form of Peregrine, derived from the Latin peregrinus, meaning "traveller" or "pilgrim". Alternatively, from the old English pirige, meaning pear tree. Pippin went much far than hobbits usually, though I think "traveller" may come also from his mental journey - from most carefree of hobbits, to guard of the citadel and friend of kings.

Meriadioc
The name Meriadoc is a boy's name meaning "sea brow". This Tolkien name is a variation on Meriadeg, a Breton name derived from Conan Meriadeg who was the legendary founder of Brittany. Merry was a staple of normalcy among the hobbits, a voice of common sense. He was a brave warrior, when needed, maybe Tolkien wanted to put emphasis on that.

Bilbo
A bilbo is a type of short sword, named after Bilabo, a city in Spain. Maybe that was allusion to Sting, a sword/dagger Bilbo found in troll cave - or just a fun name for kids, as The Hobbit was filled with fun and childish names, like Bombur or Bofur.