Alright, let me have a snap at this.

1. Whats the best class, and what is their second classes?
There is no "best" class job, all job's are useful. I'm not too sure what you mean by "what is their second classes" though. You can have a main job, and a subjob at the same time. You need to complete a quest in order to use the subjob, and they can be whatever job you want as long as you've unlocked it.

2. How many skills can you raise?
Umm... alot? There's tons and tons of skills you can raise for each job class. You may want to look around on different websites dedicated to FFXI to find out.

3. If you can't raise stats, hows that differentiate you from others?
You do raise stats by gaining levels for each job and using stat raising items.

4. Is this game better than RO?
I have played RO, and I can tell you, it's defenatly not going to be better than FFXI. FFXI is a huge place compared to, and the player base seems to be more friendly. That and there's more options to choose from.

5. Whats the max level you can be?
At the moment, the level cap is at 70. They raise the level cap at times though, so it may even get upto 255.

6. How hard is it to level up?
I'm not too positive about this, but I'm guessing through later levels it gets harder and harder and more time consuming.

7. Can you level up skills: (Ie: fishing like runescape, or smithing or whatever)
Yes, you certainly can.

8. Will there ever be PvP?
Square have said there is PvP in the game, but they just haven't activated it yet. I heard they may immplement it properly in the next year or so.

9. How much time is usually played on this FFXI? Is it easy to get bored with?
It's just a matter of opinion, you'll probably play FFXI more than you have on RO. Personally I cannot see myself getting bored anytime soon with it.

There's ALOT to do on it now, and it's only th beggining, there's going to be upgrades / expansions in the future, you can bet on it.

I hope that answered all your questions to your satisfactory, someone else please contribute because I'm not sure with some of them.