First of all, I have to say, I love Bond movies! My first Bond movie was Tomorrow Never Dies shortly after it released on video. A friend introduced me to it (I hadn't heard of Bond before then) and I was HOOKED! I was then introduced to Goldeneye 64 shortly thereafter. Back in those days, TBS would do a "15 days of 007" marathon each December and I was able to catch up on all the old ones (I watched at least several of these with @mariomaestro)!

Now as for who the best Bond is, there's no question - I've got to put Connery in the lead (where hopefully he'll remain)!
It's impossible to think of James Bond and not think of Sir Sean Connery! The man is iconic!
Apart from Goldfinger (classic!), his movies aren't my favourite of the bunch, but he's still the best Bond!

If I had to rate them in order...
1. Connery
2. Craig - There's no denying he's a great Bond. After the total cheesefest that was Die Another Day, it was great to have a serious Bond. Though I will say that his movies were hit or miss (Quantum of Solace, in particular, was disappointing).
3. Brosnan - Goldeneye is easily one of the best 3 Bond movies of all time (and spawned the fantastic, albeit dated, N64 game)! He definitely had the charisma to pull off Bond, but unfortunately his movies gradually declined after Goldeneye, culminating in the disaster that was Die Another Day.
4. Moore - he was definitely the campiest of the bunch, but he was a fun Bond. But I will say that he played Bond for too long.
5. Dalton - when I watched his Bond films as a teen, I wasn't super impressed. But perhaps now I'd appreciate them more (I really should watch them again). I've heard it described that he was a serious Bond before the audience was ready for a serious Bond.
6. Lazenby - easily last place (I can't count Niven as I've never seen him play Bond), since his only movie bored me to death when I watched it years ago. Maybe I'll try watching again some time. But props to him for getting the part without any acting experience!

Ya know, I really should binge through all of the Bond movies in order! As if I don't already have enough stuff to watch, haha!