Re: Computer freezing quite a bit.
Right click your clock in the bottom right and click Start Task Manager. Check the memory and CPU usage under the performance tab whilst playing WoW + listening to music and see if either are very high when you start to freeze up. Whichever it is that is high is what is causing your less than great performance.
What are you using for the virus scan, and what are you using to defrag your system?
Primary::: Asus M4A79XTD EVO | AMD Phenom II x3 720BE @ 3.4GHz | 2 x 2GB Corsair 1600MHz | XFX HD5770 + eVGA GTX260 Physx | 500GB Samsung F3 + 520GB Storage | Corsair Obsidian 700D | Win 7 Ultimate x64
Secondary::: Asus P5N32-E SLI Plus | Intel Q6600 | 2 x 1GB Corsair 800MHz | Gigabyte 9800GT | 180GB Caviar Blue + 250GB Storage | Win 7 Ultimate x64