I can play a external (line) input device audio, it sounds fine, I hit record, it appears to have recorded fine, until I play the recorded sound back, or save the sound to disk and play it back through any player, I get noise -=- like a static sound -=- that accompanies any sound.
You say "any player" -- do you mean any external player? I came across the same issue when using line in on my TV card. The sound from the TV application would be fine, but I'd get static on Xmms and so on. The solution was just to turn the volume on line in down.

Some ideas about your other questions (don't regard them as particularly authoritative!):

3. From the Kde manual

To launch programs when KDE is started, do the following:


Procedure 6.1.


Open the Autostart folder. By default this folder is at $HOME/.kde/share/autostart


Open a Konqueror window and browse to the program you want to add. If you don't know how to do this, it was covered in the section called “Opening a Window Containing Your Home Directory ”


Drag and drop the desired program from the Konqueror window on to the autostart folder. When asked, choose Link to create a symbolic link rather than a full copy, as this saves a great deal of disk space.


Repeat the above steps for every program you want started when KDE is launched. Remember, you don't need to add native KDE applications, just leave them open when you log out, and they will open up again as if nothing had happened, the next time you log in to KDE.


Restart KDE if you want to see the autostart function in action.
4. It should start using swap. I'd simply try it and see.

5. I don't think anyone has got SanDisk stuff to work in Linux. It's horrible, nasty, nasty stuff: it doesn't appear to be fully standards compliant. Try borrowing almost anything else. FWIW, I use a Zio reader which works fine with Maxwell and (opens camera) eFilm CF cards (and whatever comes as stock with Canon Ixus 3s.