Sounds like the problems I had when I first started out, Kayot. It definitely sounds like a dual-core processor issue. Running Vista on this laptop with dual-core AMD processor.
Even simpler than Annihilator's suggestion, try to right click your EQ shortcut and go into the properties. On the Compatibility tab, change it to Windows XP compatibility mode. See if that does the trick for you
EDIT: Just re-read your post; you have a Vista laptop but you're running XP? Okay then. If you're running XP, try changing the compatibility to Windows 98. If you're running Vista, change it to compatibility for Windows XP. That's fixed three out of three systems that I've had dual core issues with. So much easier than setting affinity. Leave binding affinity to soulbinders =P
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