I usually clean my keyboard by totally deviding electronic from plastic parts and then go to the bathroom to wash plastic part. Electro details should be cleaned in any dry way by hands or with dust cleaning tools for home usage if needed.
Freezing is usually caused by overheating of the hardware (CPU/RAM or HDD) Try to ensure that all your coolers work properly and they don't stacked in dust or powder. Perform any temperature measurement and compare them with the stable one.
