This question has come up many times in the past. Since Tesco ceased selling their Hudl tablets, there's never been any doubt that the best budget tablets for people with fairly basic requirements are those in Amazon's Kindle Fire range. If you're buying the 8" version though (as in Sharon's link) it's probably worth paying the extra £20 to get the 32 GB model (rather than the 16 GB one).
The Kindle Fire HD 8 would meet Mrs T's needs well but, if she wants a larger screen, there's also the Kindle Fire HD 10 to consider:
Amazon.co.uk User Recommendation