Godaddy has been my primary registrar for years now, and so far I'm quite happy with them.
Haven't had any issues with their systems, just a couple of payment bugs (double charge) and a problem with a .ws domain that was "double booked" but everything was sorted out quite fast and without much problem.
(even if their "normal" support could have been a tiny bit more helpfull...)
Their prices are overall very good, even if you can find cheaper registrars for some types of domains, but there are usually many discount codes you can use to get great deals on the main extensions.
Example of prices (today) pr reg/year
.com .info** .net .org .biz .us .mobi .tv .ws .name
$8.95 $0.99 $8.99 $8.99 $7.99 $7.99 $14.99 $39.99 $9.99 $9.99
** "super sale" on .info now
If you have a few hundred domain names with them you'll get assigned a personal contact there that you can contact directly if there's any issues or questions, to get even faster (and better) service/response.
I've you prefer to keep everything in one place (I don't....) then Godaddy offers almost anything you need to run a site/online business.
Their servers aren't the best or cheapest, but they're not the worst I've seen either.
TDNAM (The domain name aftermarket) is also owned and operated by Godaddy, and it's a popular place to (re)sell cheaper domain names.
They also offers a reseller service, but I haven't tested it so I can't say mucha bout it other than that I haven't heard anything bad about it from others (yet).
But one of the main downsides about using Godaddy is their "ads" for own products and "special offers" that they'll try to push on you whenever they can..
It's a pain in the a** to checkout, and you have to go through several pages of ads for other products and "special offers" to get to the checkout page..
But once you get used to it it isn't that bad, and I've started to go blind on the ads and know what to do to get passed them quickly...
But overall Godaddy is a good and affordable registrar that I usually recommend to others...