Here is my humble proposal!
I just spent about 45 minutes looking at the best options for you without breaking the bank and be ideal for what you need it for. Unfortunately there are not many in under£100 category which are worth buying. I personally detest proprietary accessories like batteries since they usually cost an arm and a leg and they are not easily available unless you go to a specific store to get them. Besides when a couple of years pass the batteries either are no longer available or are way overpriced since the user is stuck and has to get them or else they cannot use the camera.
The second thing on my mind was your options in usage of the camera, what you wanted was something which can do all the jobs nicely if not perfectly.
The third thing which was on my mind was flexibility in its usage where my main concern was its exposure capabilities and white balance options. The more flexible the camera the better the final result. Besides giving the comfort to the user of knowing that he is in control and not the idiot box instead. I would suggest to you an article I did on White Balance as it may prove useful for a first time Digital Camera buyer. The link to the article is provided at the end of this post.
While doing the research I came across a very nice option just we bit under £100 which does most of the things as anyone could ask for. The possibility of buying a decent digital camera around or under £75 is very slim and best to stay away from them. The reliability, support, quality, after sales service all the same time in one package are extremely difficult if not impossible.
So coming back to the the camera for you, I have just one with my full recommendations. If you like it by all means go for it as to be honest there is not much out there under £100 which I would consider with me own dough if I had to.
Canon Powershot A410
White Balance
If you need any further assistance please do not hesitate to ask for it
