OK so how do I make it sound good?

First, my recording setup:
P4 CPU computer at 3.4 GHz, overclocked to about 4.
Good graphics card, if that does anything at all
EMU 1212
Soundblaster Augity ZS or w/e its my card for all non-recording applications
1 gig DDR2 533 Mhz ram
Plenty of hard space
Berhinger mixer
AKG condenser mic (goes down to 20 Hz)
OK so here is the deal. My band likes to record small demos and such (for albums we go to a studio) at my place. Anyway, I was recording from my FX unit (GT-6B) and it sounded like crap, all clipped terribly and not very full and no tone at all. I was doing a cleantone slap/pop part. When using OD and distortion on some other parts, it sounded OK but not great. When I plug my Mesa 400+ into it, I get gobs of tone and everything is great, but I don't like lugging my huge cab around. Even micing a combo didn't help. I didn't do a mixdown, so this was uncompressed I think. The sound coming from the combo and phones when I was playing sounded great. What is wrong? I'm using my pretty nice Sony surround sound system to monitor, and its fine whenever I plug my Mesa into it, but could this be the problem?

 

I was screwing with the settings earlier. First I had it the same as I had it with the amp (by the way, this has modeling but I rarely use it) and the signal appeared too hot and the mixer clip light kept lighting. I turned the master down, but then all I really got was clicking when the mixer clipped but no real volume otherwise (you can kinda hear a little but the clipping pops kinda make that hard as well). I tried screwing with EQ as well. I know it can't be the sound card because it was working fine with drum mics and guiter (through the mixer). I tried different mixer inputs, but no luck. I'm beginning to think that maybe I just need to use my 400+... I also tried micing a smaller all SS combo. The sound coming out of it was just fine, but I still got the clipping. The miced combo was in front of the monitors, so it may have been the tweeters acting up and causing the clicks to be reinforced. It seems that whenever I turn down, my usable volume goes down while the clipping clicks sound the same... The gain on my mixer was all the way down, volume at 0 DB.

 

That is the volume I'm talking about.