How Do I Decide What Kind Of Web Hosting I Want Etc?

im planning to create a website right now on go daddy.
i have a few questions for the computer smartys out there:
1. for my domain name, the site is suggesting i buy the .info, .org, AND .com. is it really neccessary to buy all them or is .com enough?
2. for my web hosting, do i want linux or windows? and um..what is linux?
3. should i get the economy, deluxe, or premium plan? and should i pay for just a few months or a lot of them?
4. and is there anything else i should buy or think about or whatever before i get it??
so please try to help me out, if only with 1 or 2 of my questions.