It was kinda hard to judge the sound quality because it sounded like the Windows Media encoding was at pretty poor quality (I liked the music though!). But you definitely need some more body to your guitars; maybe try adding some mids. Did you have reverb on your rhythms? I thought I heard a reverb tail on them at one point, but I can't be sure. Anyway, if so, take it off! Rhythms work best dry and in-your-face (IMO). You can definitely get some usable sounds out of the POD XT. I haven't used the older POD models, so I'm not sure how similar/different the emulations are. If your POD has a Dual Rectifier model (called Treadplate Dual on the XT), try that. Again, I have no idea how different the emulations are, but obviously make sure your main output is set to Studio Direct. If you do have a Rectifier model, try something like:
Cabinet: Rectifier 4x12 (called Treadplate 4x12 on the XT)
Mic: 57 on axis
Room: 15% or less
Gain: around 2-3 o'clock
Bass: around 2-3 o'clock
Mid: around 11 o'clock
Treble: around 1 o'clock
Presence: around 1 o'clock
Channel Volume: around 3-4 o'clock
Output to taste
Stomp: Screamer
Drive: 15%
Tone: 50%
Gain: 50%
NO reverb, delay, compression, or anything else.
I don't have a POD XT in front of me, so those are all very rough settings from memory (and will obviously change according to your guitar's sound), but see if that gets you in the ballpark. If your Dual Rectifier model is voiced way differently than the one on the XT, the above settings will probably sound terrible. But give it a shot. Be very careful running into an outboard compressor like that; you could easily suck all the life out of your tone. I would never compress rhythms except maybe touching the low mids a little during the mix if it needs it. But everybody's different; whatever works.
Let us know how it goes. And, it is entirely possible you're just getting the best sounds you can out of that POD. I have to be honest, nothing can beat a good 4x12 cabinet cranked LOUD in a good room. That's just how guitars were meant to be recorded. But that doesn't mean you can't get some good sounds with emulation these days. Good luck!
