Well Dog, as Randy Jackson would say- You are asking questions that often have irrelevent answers. Digital recording is simply a way of storing a model of sound nemerically, and then manipulating that model, and turning it back into sound. Can you process the sound within a digital recorder? Yes. Can you do it in a computer? Yes. A digital recorder is just a specialized computer. What does it sound like when you plug an electric guitar into a digital recorder. If you know what you are doing, it can be "OK". Most people would agree that mic'ing up an amp wins, in most cases.
What's really important? ***IT'S NOT THE RECORDER***!!! What's important, really? The front end, the microphones and preamplifiers. What's more important than the front end? The room it's played in. What's more important than the room? The song. What's more important than the song? The player. Your brain is way ahead of itself. You have to build the signal chain from front to back, not back to front. If you have a great musician with a great instrument playng a great song in a great room, you put a really good microphone in front of them, plug it into a great preamp, push record, and say, "Go girl!" Far more important than the recorder are the tracking engineer, the mixing engineer, the mastering engineer, and the producer, who make all those great components come together, capture them, and then display them in the best possible light.
Where do you put the mic in front of the amp? Where it sounds good. The song, the player, the room, the axe, the amp, the mic, and the preamp will dictate where that is, and it won't always be the same. You mention a condenser mic. That can work, especially backed off in a good room. More commonly, dynamic mics are used for amp mic'ing, and many people like the mic right up against the grill, just slightly outside of the center of the speaker cone, but there's a hell of a lot of ways to skin that cat. Many times, the sound you want can be elusive, and the solution can be a mic you didn't expect in a place that wasn't recommended. Consider "The Recording Guitarist" by Jon Chappell. It's not a bad place to start for guitar recording. But, if you have a good engineer, the player, the axe, the amp, the song, the room, the mic, the preamp, you can plug it all into a top of the line Walkman, and it will rock. Good luck. The learning curve, and the confusion, starts here.-Richie