ok,well i got one of these for christmas,and i like it cause i can listen and record my stuff on my PC...and its pretty good sounding quality..the thing itself has an earphone input and i 1/4 jack input....ok what im asking is it a good idea to plug in a mic to the thing and record my acoustic playing and my singing,or is it better to play the song by itself,then playback and record my voice on it?
Unless you have 2 input jacks and 2 microphones, I wouldn't do both at the same time. Not that it won't work, but there will be no way to differentiate the guitar playing from the vocals, so you can't change the mix if your voice is too quiet or something.

The quality will just ultimately be better recording them seperately.
Electrolytes Smell Like Semen...
ok i thought so,thanks i mean i was going to like prop the mic between me and guitar and tilt my head foward a tad,but i thought that was to uncomterable and it will prolly affect my playing ability