The video stored by them - when collected by consumer camcorders can be in MPG or MOD format. This is pretty compressed (especially when compared to the much less compressed DV format video captured by miniDV tape).
I share this not because I am trying to move you back to digital tape - But since you asked, I want to be sure you know what you are getting into.
This is a bit extreme, but if you have ever dealt with digital stills, you may have experienced what compression can do. When you take a digital still with an 8 megapixel camera, the resulting still image can be anywhere from 2-4 megapixels. Even filling a large monitor, the image looks great. With broadband connections today, emailing that is not a big deal, but in the past, one would generally compress the image - again, this is an extreme - some people would compress the image down to 100k (or less. All the image data is discarded. Gone Then the receiver looks at it in a small window and it looks great - but in the same large window it used to look good in, it no longer looks goo. The data is gone. While this is not likely to happen to this extreme in the digital video environment you are heading in you do need to know that the compression applied is a LOT. The combination of this compression and fast action can cause problems with the image quality as well.
I was an IT manager i a previous life. A single hard drive for storing important data is just begging to crash. That is why there is such a thing called RAID1. Basically, two drives have identical information. The chances that both will fail simultaneously is low. When one fails, remove it from the housing, drop in a replacement and the other drive with the same data will copy that data over to the new drive.
Optical discs - DVDs come in 3 flavors:
Single sided, 12cm, DVDs hold only 4 .7 gig of data. Not very much.
Double sided, 12cm DVDs hold only 8.5 gig of data. Still not very much.
If you jump to a BluRay burner, they start at 25gig per disc - so now we're starting to talk about OK space. But that means your computer needs a BluRay infrastructure - You do not need to be recording high definition video to take advantage of the high capacity, but it is a fairly expensive solution.
In either case, the extra step of burning the discs can be time consuming - and if you need to transcode because your video editor cannot deal with the video format, well, you just ate up most of the time you thought you might save.
Making the DVD archives assumes that the video is in the same format that the camcorder captured. These data DVDs are not playable in a regular DVD player - the files are computer-readable only. Rendering a DVD playable in a regular DVD player results in "VOB" files being created. They are more compressed than the MOD/MPG files from the flash and HDD camcorders. This is how a single layer DVD can store up to 120 minutes of VOB-format video by stuffing the data and discarding as appropriate, to fit all that into 4.7 gig.
MiniDV tape, at about $3 per tape (I get them at Fry's in 8-packs for $24.99 - they are cheaper in quantities at tapestockonline.com) are the archive when you don't re-use the tape. You already know this. Inexpensive, digital format, storage with least compression - and no extra step to make the archive. A single 60 minute miniDV tape recording in SP mode can store the equivalent of about 14 gig of DV format video (thats how much hard drive space is used when the video is imported to the computer).
As for the zoom range, yes, the standard definition cams do have a higher multiplier than the high definition cams. There are probably lots of reasons why - one way around this if you decide to go the high definition route would be to use an add-on tele-lens. I use a 2x tele lens on occasion. It takes my 10x HDV cam up to 20x... Steadiness is pretty much impossible when handheld or monopod - a fluid-head tripod works pretty well, though.
As for the software in the box - generally not very good. For the Windows environment, Sony Vegas is pretty good (for the low-end "Studio" version) and Adobe Premiere is very good along with the Vegas Pro version - there are lots of other titles and all will have some sort of learning curve. But if you want to discuss this, it is where I would get off the bus - I gave up on Windows doing any real work many years ago and all my video editing is done on Macintoshes with Final Cut (and occasionally iMovie). I have Windows computers around the house (recently got a HP EliteBook 8530w with a 1394 port to see how the other OS and various applications deal with various video imports... I must say, it is better than it used to be, but still no where near where Macs are).