Empties batteries in 2 minutes

Always charge batteries before using it for the first time, or if you have not used it for a long period. 3 months is a very long period.
Always charge sets of batteries (2 or 4) together.
Do not use alkaline batteries unless it is absolutely necessary. In some cases, alkaline batteries may have a shorter service life than NiMH. Alkaline battery performance is limited, especially at low temperatures. The use of NiMH batteries is recommended.
Never use manganese (Zinc-Carbon) batteries in electronic devices.
These batteries are only to be used in flash lights.

Check the contacts of the battery and in the battery compartment of the camera. They all should be clean and shiny. You can clean contacts with a dry cloth or cotton swabs. Never use anything sharp in or close by a camera.

Try another set of batterys, can you clarify what do you mean with power light? does the camera function at all right now?

In DSCW7 Camera, you can use NH-AA-DA (Ni-MH) batteries (this is the supplied one) or Alkaline batteries.
With the LCD screen on, you can capture upto 190 minutes when using the supplied Nickel metal hydride batteries.
When using the Alkaline batteries, the life is only for 35 minutes.
This is a normal operation of the Camera.

The actual battery life will vary depending on how the camera is operated and what functions and types of batteries are used; using zoom and flash frequently will shorten the battery charge.

The average recording time of the battery as listed on the packaging will vary due to several different factors, including ambient temperature and the power consumption of the camera. The battery package states the power consumption specification needed to achieve the average recording time. If the camera power consumption is more than the specification on the battery packaging, the average continuous recording time will be lowered.

Also, batteries discharge faster when used in cold weather conditions. In cold environments, it is recommended that batteries be kept in a warm place before using. Sometimes batteries may recover some power if they are warmed up after being in the cold.

When using alkaline batteries, do not mix new batteries with used batteries. Doing so may reduce the battery life.

(Nice camera :)

Typically, if the camera worked before the batteries were replaced, then non-function after battery replacement comes down to two items:

1) the batteries were inserted wrong way (with the wrong positive (+) or negative (-) end up or down. Check the inside of the battery compartment to see a little diagram with the + and - sign. Or else look in camera manual.
Fuji s8100 requires 4 x AA batteries, either Alkaline or Ni-MH rechargeables.
The two outer ones should have positive (+) bump UP, and the two inbetween should have the negative (-) smooth UP.

2) or the batteries are not new enough or not fully charged.

Also, when you replace batteries, never mix Alkaline with Rechargeables, and do not mix Old with New. You must go with either 4 Alkaline, or 4 Rechargeables, and either be new or just recently charged up.
Sometimes dirt may hamper the contact, but not usually.
And do make sure the battery cover latches down snug.

Are you still using alkaline batteries? If so, alkaline batteries just don't have the power for more than a few pictures in a digital camera. Some may also have reached their shelf life, and though right out of the package may even have problems just powering startup of the camera. Digital cameras that use AA's for the most part should only be used with rechargeable NiMH batteries. If you read the camera's instruction manual concerning batteries, you may see the same recommendation.
Keep in mind rechargeable batteries will save you money in the long run over alkalines, AND they'll last for at least 100 pictures per charge (and probably many many more). You'll be very pleased with their performance, and may be angry with yourself for not buying them sooner. When at the store, look on the package for a power rating of at least 2500 mah.

Remove battery for a minute and insert it again.

There is a Battery Type setting in the Menu of your camera.

Do the following:
- Press Menu/ Ok button
- Go to Set Up 2
- Scroll down to Battery Type

Two options under Battery Type:
- Alkaline- if you are using non- rechargeable battery
- NiMH- if you are using rechargeable battery

This happened to me too. I did some research and if you were using anything other than alkaline or NIMH batteries (I was using Nicd rechargables) it will fry the circuit board. That's Sony's way of making sure you use their rechargable batteries only (or buying costly alkaline). Our cameras are fried. Time for a new one.

Alkaline batteries are not capable of outputting the level of power required for your camera to operate. Your daughter's camera may have lower requirements and be able to function properly using alkaline batteries. Your standard alkaline battery outputs about 700 milliamps of power when they are brand new. A rechargeable NiMH battery can range from 1200 to 2700 or even 3200 milliamps max power output depending on the quality of the battery. Most compact digital cameras that accept AA style batteries are designed for these high-output rechargeables and will not function for very long even on fresh Alkaline batteries. David Millier Advance Camera Repair

I use professional $70k cameras for work and it's the same type of thing. If you're not using it, take the batteries out. With my A75 I have some energizer 2200mpa rechargeable AA's and the seem to last about a month or so. If I happen to be "cranking" through pictures though (upwards of 300-500) in one sitting, it will suck them dry. The rechargeable batteries last longer than the Alkalines. I was heistant with the rechargeables but for $20 I picked up a 15 minute charger and the 2200mpa AA's, now I recommend them to everyone with a digital camera. Digital cameras eat Alkaline batteries in a hurry.