Namecheap is pretty good and very reliable while, at the same time, is also inexpensive. I haven't heard much about fabulous to comment on it. Luckyregister is less well known that Namecheap and may cost less but isn't that reliable.
Registering a Domain name is very easy as there are numerous sites for it... I have not heard much about Registarjudge.com. I used to register my domain name ay XnYnZ.com where they provide services like domain transfers, Private registration etc.... You can make a use of it if you wish..
I'd like to know this too. I've got a couple of domains with GoDaddy, but they haven't been the greatest company (their email servers SUCK!). We've also used 'Name' at work and they have been OK to be honest. If you've got a host that's provided you with great service then maybe just buy to domain though them?
I only use GoDaddy. Right now I have two domains with them. I can't talk about their hosting because I have never used. The same goes with their mail service.
Last year I used register.com but I would not recommend them because their prices are really high (don't know their current prices but last year a dot COM was about $25 while at GoDaddy the price was about $10).
I prefer hostgator.com . They've nice support, the price are low. There are also some reseller plans. The sitebuilder provided by hostgator is really easy to use, I've made a website for my gaming community and I never had any downtime. I will surely recommend you hostgator.