Direct boxes, preamp out, line out ,effects send computer re

answer to a few simple questions, though maybe someone here could help out:

Looking to record a signal from a guitar amplifier to a PC (as well as a digital hard disk recorder). I am aware that in order to plug into a computer the signal should be line level. Is this also true for digital recorders?

Is the "preamp out" jack a line level out? Can I plug that right into a PC sound card (with a 1/4 to 1/8 adapter)? Can I plug it into the digital recorder?

Is the "effects send" jack line level? Can that be plugged into a PC sound card (with a 1/4 to 1/8 adapter)? Can I plug it into the digital recorder?

I read that preamp IN/OUT is basically an effects loop, do not know if that is accurate. If so, it makes the answers to both topics the same.

The vague idea I have gotten so far is no, these outputs are not line out. A direct box is needed.

The direct boxes I have seen all seem to work like this: 1)plug the instrument into the direct box IN; 2)plug the direct box OUT into the amplifier; the remaining output is an XLR/mic output that would then need to have an adapter which allows me to plug the signal into the computer/digital recorder. My friend's mixer has XLR inputs, so this last step would only apply to a PC I guess.

The direct box manufacturer's websites I looked at said nothing about connecting to a computer, only a PA. I don't know if I am understanding all of this correctly, so perhaps I am looking at the wrong kind of direct box.

It would seem to me that if you are plugging the direct box into the amp input (between the instrument and the amp input), there is no way to get the signal that is being output. I would assume you would need to disconnect the speaker cable from the amp and put it between those two components. But I am completely mystified at this point.

My 15W solid state practice amp has a line out, but my friend's Hot
Rod DeVille doesn't, only a preamp out. I don't understand why a more expensive amp can't incorporate such a simple feature. Perhaps it has to do with tubes? What the heck is the preamp out used for?

This is driving me crazy. Any help would be greatly appreciated.

Take a trip down www.amptone.com then come back and ask away.
The site will probably explain about 90% of what you need to know but also put 900% more unanswered questions in your head.
The easy way: buy a modelling amp!