No, the Canon 5D Mark II records video at a maximum resolution of Full HD (1920 x 1080) at 30fps.
Yes, it features a magnesium alloy body with dust and moisture resistance, though it is not fully waterproof.
No, the 5D Mark II is a full-frame camera and is only compatible with Canon EF lenses. EF-S lenses will not fit and could damage the mirror.
Using the LP-E6 battery, it provides approximately 850 shots per charge based on CIPA standards.