Forum Tips and Invite System

[sabrebattletank]

So I know there are a bunch of mods here and that a couple of you have experience in forum administration. I'm looking for a some advice as far as forum administration goes, as we're thinking of making a Power Pirate forum invite-only as a sort of logical next step from the only nominally-existent state it's in now, with the end goal of a fully open forum in the "near future," whatever that means. The invite system would be temporary.

What tips do you have about getting a successful forum started and keeping it going?
If you were to start your forum over again, what would you do differently and why?
We're currently built off of MyBB Version 1.4.9 Simple Machines Forum, but we're open to exploring different ones. Why did you choose the forum type that you did?
Do you guys have any recommendations for forum programs, capchas, invite systems? (we're hoping to have for the moment a *users with x posts can invite y people via e-mail* type of system.)

Edited for clarity.

[TwinShadow]

I've help set up phpBB, SMF, and MyBB forums. I used to modify phpBB heavily back in the day it was pretty popular. It still is today, but I think they're losing it now, and I've long since ditched it. I've moved onto SMF as an alternative since it was the next best thing I can find.

The way people run their forums is different between people. Depending where I host what forum depends on a number of things. 1. What kind of forum do I want? What kind of content do I allow guests to see, registered, and so on. 2. Pick a forum system and mods/packages/themes that would fit the forum content. 3. What rules would I place for everyone?

I use captcha on all forums I run or help run. I use a strong captcha that is not easily figured out by bots to reduce them drastically. I don't agree with invite-only systems personally since I like forums to be out and open for everyone. But again, that does depend on what kind of content you want to allow. And because I have some experience with modifying forum files, I'm quite comfortable with modifying files for a completely different forum system, even though it is a slightly different learning curve.

As far as recommendations for forum software goes, you will never get a straight answer. Some like phpBB, others with SMF, MyBB, vBulletin, IP.Board (Invision Power Board), and other forum systems. Personally speaking, I'm fine with either SMF or MyBB at the moment and am no longer recommending phpBB. (reasons I will not disclose) I have never liked forums where you have to dish out hundreds of dollars for a license and paying for upgrades. Its just too much money to waste on a forum where you can get the exact same thing, for free.

My current forum runs SMF like you see here. This makes it easier to get any help from a couple friends here in case I need it, and also allows me to teach new people the basics of running an SMF forum. I can still do things on phpBB, but I choose not to.

[sabrebattletank]

I don't agree with invite-only systems personally since I like forums to be out and open for everyone. 

Thanks for the tips! We're only thinking of an invite system as an intermediary stage to find some of the bugs without having it open to the general public. Essentially, "beta." I'll edit the first post to reflect that more clearly.

[AHadley]

I used to run an MFF forum, but it went badly wrong and it collapsed when (I think) the company went bust.

[sabrebattletank]

We've selected SMF. Wewt.

[Nielk1]

I use phpBB3 and SMF2, though my SMF2 site is far from ready as I have not had much time. Both use completely different modding systems and come with different standard material. I like both. phpBB3 is good if you have the time, SMF2 is good when you want ease of use. phpBB3 is good when you want a forum, SMF2 is what you get when you want a forum, a calender, etc.