and some info may be repeated from earlier posts.
The Sony HVR-A1 is a miniDV tape based camcorder. The "DV" in miniDV = Digital Video. The video stored on the tape is as digital as digitized video store on flash memory, hard disc drive or optical disc - but the DV (and HDV) formats written to the tape are a lot less compressed than the other formats used by consumer camcorders that use the other storage media.
Generally, the A1 (and the consumer-sibling HDR-HC1) are "point and shoot" pretty much like any camcorder - useful for good lighting environments. The A1 does have some controls through the menu and externally, so it helps to get to know the camcorder when video capture situations are less than ideal or you want to try other stuff.
The single ring on the lens barrel can be assigned a function - so it is a "shared" ring. Most commonly, it can be either manual zoom or manual focus. I usually assign manual focus because there is a zoom rocker switch that is easy to use and access near the eyepiece... or by using a couple of buttons on the left side of the LCD panel That's another thing - it has both an eyepiece and a relatively large LCD panel to monitor your shots.
Manual exposure control is accessed using a button on the left front of the camcorder - when the camcorder is recording. During video play/back/review, that control becomes the playback audio volume control.
The photos that the A1/HC1 can capture - when the camcorder is not capturing video - are regular 4:3 aspect ratio, low resolution by today's standards - pictures. I find it much better to capture stills while capturing video - they are in widescreen, just like the HDV format video (even though the resolution is not very good). The A1 dropped the built-in flash that the HC1 has. It is apparently where the stock XLR adapter mounts.
I *think* the U version of the A1 will be closest to your P version since Japan uses NTSC video standards. The Operating Guide for the HVR-A1U is available for download from Sony's professional site at http://pro.sony.com/bbsc/ssr/cat-broadcastcameras/cat-hdv/product-HVRA1U/
and click on the "Resources" tab.
There's lots more, but you need only read through the manual of the P or U localized versions to learn about how much more the camcorder can do. I learned to use this camcorder. So yes, "average intelligence" novice users can easily master it - especially in "point-and-shoot" mode.
As a miniDV tape camcorder, assuming you want to edit the video you capture, you need to connect the camcorder's DV port (not USB) to the computer's firewire port (not USB) with a firewire cable (not USB). USB-to-firewire cable/converter/adapter things do not work.
Firewire, DV, IEEE1394 and i.Link are all the same thing. They are not USB and should never be confused with being "compatible" with USB.USB is bursty; firewire streams.
And your video editor (in the computer) needs to be able to deal with HDV format video - most can, but we would need to explore your editing plans
Other useful items:
At the back of the camcorder, near the eyepiece, there is a LANC port. This is used for a wired remote that can control power on/off, record video on/off, zoom, focus - and depending on the controller, capture photos. Sony, Varizoom, Libec, and several others make useful LANC devices. The actual control mounts to a tripod handle and helps make video capture a lot easier. I use one when the camcorder is too far away to control (like on a camera crane).
On the left side of the camcorder, the USB port allows connection to transfer still from the (ProDuo) memory card (slot is on the right side of the camcorder near the lens barrel).
The right side of the camcorder - near the lens barrel - there's a 1/8" (3.5mm) stereo audio input. This is where the XLR adapter plugs in so XLR mics can be used. Below this is a headphone jack for monitoring the audio being captured. The manual audio gain control is buried in the menu, yet another reason to use a XLR adapter (with control knobs you can easily reach).
The *only* thing I do not like about this camcorder is that the miniDV tape feed into the tape mechanism is from the bottom of the camcorder. If the tape is full and needs replacement and the camcorder is mounted to a tripod or something else, then you need to removed the camcorder from the tripod to be able to replace the tape. A 60 minute miniDV tape will hold up to 63 minutes of HDV format video. I got a "spacer" from bhphotovideo.com that mounts between the camcorder and tripod to lift the camcorder from the tripod mount so changing tapes no longer requires dismounting the camcorder from the tripod.
If does have a small (37mm) lens filter diameter and small single imaging chip, both of which are more like consumer cams so low-light behavior can be grainy, but for a 10-year old camcorder, the HDV format is still awesome and (IMO) better than the high compression AVCHD format consumer cams use.