Eager-2-Please, wine is pretty personal. I'm very in to wine, at my "worst" I had over 1800 bottles, needless to say i was a little shocked when I was counting them up and have stopped buying now and focussing on drinking ! All the suggestions you have been given are very good. Wine can range in price from £5 to over £100 and for French bordeaux or burgundy or Californian cab savs you can pay silly money for a bottle; I mean £1000 per bottle silly ! I canot afford that price tag, but I've tasted many wines over many years. Depending on what you want to spend here are a few suggestions, but only you will know what your friend is likely to like.
Pinot Noir is one of my favourite grapes and different from the usual buys and has an interesting flavour that is quite unique. At £10-£20 you can get an excellent NZ pinot noir, the NZ wine producers are generally all quality driven. At £20-£30 you can pay for a top-notch NZ pinot noir and Mt Difficulty is one of my favourites, but there are others such as Roaring Meg, or the old fall back of Cloudy Bay, but they are more well known for their white sav blanc; again any NZ pinot noir in this price bracket will be pretty guarenteed to be excellent.
If you want to stick to pinot noir, but from France and burgundy then the price is a little higher and you will pay from £20-£50. There are many "sections" to burgundy and you would be best to go in to a wine shop to purchase this and ask. Burgundy is my all time favourite and I like the more "etheral" styles like Chambolle-Musigny, but I also like Vosnee and a range of others; I also tend to favour certain producers as you build up confidence in them.
All pinot noirs are easy to drink on their own or with food.
Spanish red is always a good buy and they do all the "cellering" for you. Rioja is only released when it's mature and ready to drink; the Spanish wine controls dictate what is required and the subsequent naming. You can get a decent Rioja from £20-£40. You need to look for some additional words on the bottle. Crianza is the youngest aged Rioja and is ligther in style and drier, personally I prefer this. Next is Reserva which has had more ageing in Oak barrels and the vanilla and richness is starting to show more. Gran Reserve is aged further and so more vanilla and oaky again. They are all generally very smooth, easy to drink on their own or with food.
If we are talking big bold wines based around Shiraz/Syrah grape then you can get some great wines both old and new world in the £20-£50 price range. Australia does excellent Shiraz and the more artisanal wines are drier and, in my mind, better wines. D'Arrenburg is a great producer as is Lehman, Two Hands, the list is pretty long. Again you can be pretty certain of the quality regardless of the winery. Australian Shiraz is very fruit driven and rich and bold and for some "too much" to drink on it's own, but goes great with red meats. The alternative is to go for a French Rhone red although these are usually blends of different grapes, they often have Syrah (Shiraz) as a key component. Any Chateau Neuf du Pape would be rich, heavy, fruit driven, but much drier than the Australian "equivalent"; again better to drink with food. There are a number of Chateau, the best being Beaucastel, but Sixtine and Clos du Pape are also very good as well as a range of others.
There are many other wines, grapes and regions in the world, but those above should give you a good selection depending on what wine your friend likes.
Good luck and I'm sure she will enjoy the wine you finally chose.