Kernal questions to better understand.
 

I apologize if the topic seems alittle vague I did not want to make it overly long. Only enough to give you an idea of what I was looking for in regaurds to information.

I had afew questions regaurding updates and such and they are as follows.

1) When I do my yum updates and for example got a new kernal update to 2157 I beleive (correct me if I am wrong). When the system rebooted after installation I recieved a graphics card error and was not able to boot into gnome until the system did an automated recovery and did it's own video driver recovery from defualt drivers. Now I DO understand that the root cause for this was that I had the kmod-nvidia drivers? RPM? installed. (Also had troubles with kmod-ntfs)

My question relating this is, Do I need to do a "yum remove kmod" everytime I go to update the kernal to ensure I can boot back into the new kernal and then do a "yum install kmod" once the installation is complete? If so is there a specific reason as to why these drivers fail when all others on the system seem to accept the new kernal update?

Secondly, While being new to Linux in general I have seem some talks of "compiling of the kernal". I was hoping to gain more understanding on what exactly this means some benefits and flaws and how this differs from when I do a "yum update" and end up getting a new kernal build (if they are not the same thing). Thanks for your time. I appreciate all the help you have all given me in the past!

Also on a final note. Can anyone explain why everytime I update I always have 2 choices for each update on my grub loaders one 21XX and one for 21XXSMP. I know that SMP stands for duelcore but why would the system load both when it KNOWS i have duelcore?

Sorry forgot to say I was using Fedora 5 2157 kernal release I believe.

It installs both, because on dualcore SMP may fail or not fail. It is for dual-processor anyway..
About compiling=building kernel. When you download binary from distro vendor, you get standard compiled kernel. When you compile yourself, you download source code (it is readable - and editable, unlike binary form), possibly apply patches like suspend2, check everything you need that is in kernel, uncheck things that just add bugs on your system and build it - with optimizations for your processor family, not generic 80386 processor.

Once you compile a kernal can you then still add programs and applications properly? Or everytime you add an application does the kernal need to be recompiled?

Does compiling your own kernal give you that much of an improvement system performance wise?

While I like the idea of being able to literally pick and choose what applications and software is running on my machine (while I have alot of learning to do yet before I can properly understand the basics of what I need) Would this not also be a huge security risk for a machine being connected to the internet if you do not truly know how and what services and applications you should be running?

It's kernel. Yeah, you can install applications as normal after compiling a new kernel (or recompiling your old one). You don't need to recompile the kernel every time you install new applications. If you compile a new kernel though (or recompile your old one I would think), you may need to recompile and reinstall some software (not normal software, just things like the NVIDIA drivers, or NdisWrapper for example).

It really depends. Sometimes it gives you some rare features you like also. Or lets you get rid of initrd. By the way, initrd is a thing to ask about before you fail to boot, not after - if you use Fedora. About huge security risk - get bastille or something with similar name. It will close most network applications from the outer world. A good start, I think - gives time to learn..