What are the best packages in R or most comprehensive packages in R for option pricing and working with options?
You may want to browse the Task View for empirical finance, which lists many options-related packages.
As for concrete suggestions: I have worked a lot with
in the past, and I have found it a reliable and stable package.
Perhaps I may also suggest
NMOF, which I maintain. It
provides implementations of a number of models
(Black/Scholes/Merton, Merton jump-diffusion, Heston, ...). It also implements the approach of Bakshi/Madan (2000) for pricing based on the characteristic function. The implementation is essentially the one described in this paper on Calibrating Option Pricing Models.
Besides those mentioned by Alex C., the package 'RND' provides various tools for computing risk-neutral densities from option prices, and also provides some pricing functions for various models. RND package on CRAN. The package 'VarianceGamma' provides tools for, inter alia, fitting a variance-gamma distribution to historical data complete with automatically generated histograms and QQ-plots. VarianceGamma package on CRAN.
You may want to investigate, among others, RQuantlib, derivmkts, fOptions, OptionPricing, M4FE. I have no detailed information about these, I have just seen or heard them mentioned (here or in other places).