Leopard on a G4 = Bad idea?

Hey guys. I have two Macs: an Intel dual core 17" iMac, and then a PowerBook G4. on the iMac Leopard installed and ran great. Everything works perfectly and I'm overall very happy with it. On the G4, however, things are a little choppier; the dock is noticeably laggier, expose lags a bit, typing in iChat sometimes hangs behind my typing (usually when I have a game open too). Another thing is the game I am playing (okay, its WoW, I admit it) has strange graphical anomalies now that I did not have in Tiger and renders it almost unplayable.

Anyone know anything about upgrading on a G4? Should I just go back to Tiger or are there fixes for these issues?

Well the Dock lags on a MacBook (intel CD), so I am not surprised it does on a G4.

What video card does it have? I suspect that some are not dealing with core animation so well, or Quartz GL.

How much memory does the G4 have? (I'd suggest maxing it out, just as a matter of course these days, for any G4 Mac.)

And what's it's CPU speed? An original 12" PowerBook (867MHz) is about the slowest system that can run Leopard, so it might just be beyond hope.

Hardware Overview:

Model Name: PowerBook G4 12"
Model Identifier: PowerBook6,8
Processor Name: PowerPC G4 (1.5)
Processor Speed: 1.5 GHz
Number Of CPUs: 1
L2 Cache (per CPU): 512 KB
Memory: 1.25 GB
Bus Speed: 167 MHz
Boot ROM Version: 4.9.0f0
Serial Number: 4H5240EZRJ5
Sudden Motion Sensor:
State: Enabled
Version: 1.0


GeForce FX Go5200:

Chipset Model: GeForce FX Go5200
Type: Display
Bus: AGP
VRAM (Total): 64 MB
Vendor: NVIDIA (0x10de)
Device ID: 0x0329
Revision ID: 0x00b1
ROM Revision: 2122
Displays:
Color LCD:
Display Type: LCD
Resolution: 1024 x 768
Depth: 32-bit Color
Built-In: Yes
Core Image: Hardware Accelerated
Main Display: Yes
Mirror: Off
Online: Yes
Quartz Extreme: Supported
Display Connector:
Status: No display connected