If you haven't already, get your head down in front of the cab as you play, and listen to the sound coming out of the speakers- it sounds different to how you hear it in the room.. you'll probably have to make adjustments to the highs and the presence to get it to sound better down there. And as others have said, whack a pair of headphones on, turn them up so you can't hear any outside sound, and move the mic around as you play- with the mic closer to the centre, you'll get a brighter sound, further to the sides it'll be darker and bassier. If you've got an open backed cab, try placing the mic in the back of it, that can produce some nice results :)
It could be down to the speakers in your rig- my 1936 with GT12-75 speakers sounds horrible when mic'ed, but the open backed 2x12, with eminence speakers in sounds much better. If you've got a couple of cabs, try them out. Personally, I only like to use my Pod to record at night, and usually just to toy with some ideas; I much prefer to record stuff with the amp and mic- modelling just doesn't do it for me (apart from some clean stuff).