[GC] Paper Mario TTYD - Hd Texture pack - Having issues with the visuals

[chibiwhitemage]

So I installed the HD texture pack, and made sure to name the folder correctly, but for some reason, the game ends up looking kind of a little crunchy for lack of a better term when I make the window bigger. I'm very new to emulation and was super excited to play pm ttyd because my gamecube sadly stopped working recently. I was wondering if there may be something wrong with my settings? I'll post all of my settings below so everyone can know what I've got set up.
Graphics:
General:
Back end: OpenGL
Display:
Full screen Resolution: Auto
Aspect Ratio: Auto
only thing checked: Auto adjust Window Size
Enhancements:
Internal Resolution: Native (640x528)
Anti-Aliasing: None
Anisotropic Filtering: 1x
Post-Processing Effect: (off)
Checked: Scaled EFB Copy
Stereoscopic 3d mode: OFF
Hacks
Ignore Format Changes
Store EFB Copies to textur only
Accuracy: Fast
XFB: Disable
Other: Fast Depth Calculation
Advanced
only thing checked is load custom textures
I also did make sure to turn off the "Enable dual core" for pm ttyd because a cursory google search mentioned turning that off, and of course I unchecked the disable bounding box option too. I also have the widescreen_hack under gecko codes, but this has appeared to not really do anything? Sorry I'm very new to this and I'm sure it's something small and silly I'm doing wrong, but I really hope that someone here can assist me.