Hi Ray. While I'm no expert on this for sure, I think this forum might be a better place to learn a lot on photography techniques that can sharpen your skills and give you some good pointers.
Try:
http://www.photochimps.com/vb/
http://www.nwphotographers.net/
http://www.usa.canon.com/dlc/controller?act=HomePageAct
Otherwise, in a "quick as I can" response, I'll try on a few of your questions...
1. SHUTTER SPEED basically means, "how long you want the shutter to be open." This is a very elementary way of describing it, but think of it this way... the "shutter" is kind of like HOW LONG YOU WANT THE CAMERA'S EYE TO REMAIN OPEN. So, the longer you leave the camera's shutter open, the more motion you can capture, and thus, some of the pictures you've seen where it looks like people have managed to capture tons of lightning bolts all in one shot. Probably 99% of all lightning pictures are actually captured this way. Instead of trying to "catch" the lightning, one can just use a remote or a camera that will allow you to set the shutter to remain OPEN for 10, 30, 60 seconds, etc. and just let the lightning expose itself! It's quite easy, actually!
2. Exposure is also known as "Aperture," and is kind of thought of as how much light you want to expose the film to. Think of it maybe as, "how wide do you want the camera's eye to open?" And if you're going with a digital or film SLR, the aperture ability is totally dependent upon the lense's ability to allow light in. Point and shoots have the preset limits that you can adjust, but it's sometimes dependent upon your focal length, or amount of "zoom" you're doing.
The magic trick in photography isn't really that technical at all, it just takes practice... lots of practice, and after all these years, I'm still practicing!
Getting the perfect photo is a balance of just the right aperature, or "exposure," coupled with shutter speed, and a combination of other techniques. You'll learn it, so don't sweat it. Take your time and enjoy photography. Again, there are a lot of pros on this forum that can offer some great advice, but I hope this helps some. Visit the forum links I gave you, as there are some pros on there as well that can help you with landscapes, portraits, etc. etc.
One offer of advice I would give is that if you're looking to do lightning pictures like you stated in your questions, you will need to get a camera that allows you to adjust both the shutter speed and aperature. I would strongly recommend a digital or film SLR camera. Start with an entry level one, like the Canon K2 35mm film or if you want digital, both the Canon Digital Rebel XT or the Canon Digital Rebel XTI are good and less than $1k. Others may prefer Nikon, Sony, etc. and that's totally up to you. Bottom line, just get a good camera that will allow you to adjust those settings. A very simple point and shoot will not do the trick for lightning photography.
Good luck, and hope to see some of your pictures posted real soon!
