[Samsung Galaxy S (4G Model)] stephen_w:
I'll do my best to answer this; hope I don't skip anything :)

Can a kernel be flashed without a rom and vice versa?

- The kernel is a traffic cop. It is what controls the underlying hardware in your phone, on your tablet, or on your PC. It handles things like memory management and allocation, access to hardware, process scheduling, and much more. You can flash a kernel onto an existing ROM (for example, Gingerbread VUVKG4 ROM with a modified KG4 kernel that has root access). The kernel you flash replaces the one that's already there. When you flash a ROM, it has a kernel already in it.

Does it erase all saved data to flash a kernel? A rom?

- Generally flashing a kernel does not wipe any of your data as you're only replacing the kernel. Flashing a ROM can wipe your data; it really depends on what you're flashing. It's always good practice to make a backup before flashing unless you've nothing on the phone to lose. Flashing a ROM that does wipe your data will not wipe the contents of your sdcard, it wipes the /data and other partitions on the phone's internal memory/storage.

The designations KD1, KB5, KJ6, wtf do these represent?

- Versions. Generally ROMs for our model of phone (Galaxy S 4G, SGH-T959V) have a name like VUVKB5, VUVKD1, or VUVKJ6. The last two characters correspond to a certain build/version number. The more recent the last two characters the more recent the build. The builds for our phone were on 2.2 (Froyo) through KD1 then went to 2.3 (Gingerbread) starting with KF1. Gingerbread required updated boot loaders for the phone. Without the proper boot loaders the phone wouldn't work.

What is firmware version 2.2.1? Does this dictate what kernels/roms will work?

- 2.2.1 is Froyo. It's a version of the Android operating system (OS). It does not dictate what will work, per-se. Rather it's telling you what version of the OS your phone is currently running. If you were to try and flash something, say a kernel, you'd definitely need to know what version you are on so that you flash a kernel/ROM for that version. You can upgrade to newer ROMs, though, say to go from 2.2.1 (KD1) to 2.3.6 (KJ6). You just have to make sure you have all of the right pieces in place first.

My phone came stock with

Baseband version: T959VUVKD1

after an unsuccessful root, it now it has

Baseband version: T959VUVKB5

What's the difference? Is my new one better?

- The "new" one is actually older, which means it is missing bug/performance fixes and the like.

My kernel is now 2.6.32.9

Wasn't stock kernel 2.2.1?

- Confusing, isn't it? :) The 2.6.32.9 is the kernel version & 2.2.1 is the ROM version. When you upgrade ROMs there's a good chance the kernel version will change, too, but not necessarily. They are independent numbers but kernels/ROMs are dependent upon one another. Clear as mud, right?

Why bother switching kernels/Roms in the first place? It seems like it's just a big headache. Launcher apps seem to provide more customization then alternate Roms. What gives?

- It's a personal preference most of the time. You could upgrade to the latest release ROM by Samsung which is VUVKJ6 using their Kies Mini software. It's Gingerbread based, faster, better battery life, wifi is a little weaker. Just make sure you backup any information you want to keep first. I generally keep my contacts synched with T-Mobile or Google and after a data wipe they sync back to the phone.

As for flashing custom ROMs you'd have to read up on the different ones to see if they interest you. Some increase performance, some have mad themes wrapped up in them, some have better battery life, some do their best to roll all of that up into them.

In short, you don't have to flash anything. The development community here enjoys doing it though despite what headaches it might bring. It enables us to hack/tweak the phone to see what it can do, what performance we can wring out of it, etc. I've learned a lot in the little time I've been in this community and have a TON more to learn.

I've spent a LOT of time dicking around with this new phone (my first smartphone) and I love the fact that it is customizable it but it takes up too much time to have to read up on everything, flash, then re load all my icons, screw that. I just want to know what is the best, fastest, simplest, most customizable rom/kernel combo up front, or I'm going back to stock, I have to believe that they designed the stock OS around the phone to maximize effectiveness.

- Unfortunately reading up on it, trying ROMs out, and going through some trials and tribulations is a part of the process. Which is the best ROM is strictly subjective so you'd get a bunch of different answers from a bunch of different people.

The best thing I can suggest is, if you're really interested, to take the time to read the stickies in the different forums (General, Q&A, Developer, etc.). They contain a plethora of information that will actually help you to avoid a lot of the problems. Read some threads on different ROMs & issues. You'll find a lot of "I had this problem" followed by the developer or someone else saying "Yeah, I fixed that" or "here's how to avoid/fix it". Utilize the search feature; it's there to help. The more research you do on your own the more you will learn and the less likely you'll get flamed by anyone for not trying to help yourself before asking for the help of others.

Welcome to the forums. Best of luck to you.