I'll add my voice to the chorus of "Welcome to the Forum" folks. While none of the things I'm about to post should be taken as advice, they are things that seemed to work for me....
Do... know that there is the possibility of a good life post AN. While getting told that you have a benign growth in your head can make you feel like you've been kicked by a cow... there are thousands that have gone through this and managed to have great lives afterward. I don't know if there are support groups on that side of the Atlantic but if there are, find one and go to it. You will meet folks in the various stages of this journey and be able to see first hand that life can be good.
Don't... obsess about it to the point of blocking out everything else. Yes, do the research (reading all the info on the ANA.org pages is the best place to start) but limit the amount of time devoted to it. Having a somewhat obsessive personality, I found that I had to set up a time limit for my research. I put a limit of 30 minutes a night on the computer obsessing and researching AN"s. If a question popped into my mind outside of those 30 minutes I wrote in on a note in my PDA (a small notebook would also work for this). By writing it down, I could then put it out of my mind without worrying about forgetting it. Then during my 30 minutes of research time I could look for the answers to the questions that had come up.
Do... find a person in your life you can talk to about this on a face to face basis, preferrably one that has gone through it already. Your ENT might be able to give you some advice on finding other folks. The hospital might run support groups or have a bulleting board (physical or electronic) where you could post a soliciation.
Don't... neglect to explore all your options. Ask to be given an appointment with a radiologist (or whatever they call the guy that radiates the AN to discuss all the aspects of using radiation as the treatment, if treatment is needed. Surgeons like to surgeon, they like cutting stuff out and sometimes see all other options as inferior to just cutting the thing out. The radioactive guy will probably stand aghast that oneone would choose to have their head physically cut into when he can just go in there with his magic beam and zap the growth with no fuss or muss. It's your head.. understand all your options.
Do... take generally good care of your body. I'm not saying you have to become a super nutritious macro-biotic health guru or anything (though if you chose to...) but if treatment becomes necessary then a generally healthy body will recover from the trauma of the treatment better and pretty much all treatment options entail some type of trauma. One thing that stood out during all the pre-op talking that happened with the various hospital people was they all seemed happy about the fact that I don't, and have never, smoked. I got the impression that if a surgical option is used, smoking greatly increases the chances of complications... I guess it really hoses up some of your body chemistry. If you smoke, that might be something you talk to your doctors about...to see what they say.
Don't... stop living your life. I haven't seen any research that suggests you can make your AN worse by doing any activity the rest of your body can survive. Of course, if you're doing an activity that the rest of your body is unlikely to survive, then making your AN worse is probably the least of your worries. As others noted, if your AN is affecting your balance system then this could cause some limitations...or it could let you get more out of your rollercoaster dollar (pound) than anyone else on the ride. Some folks ride rollercoasters to give themselves temporary wonky head... some of us with AN's get it for free.
Do.. make sure you keep coming back to the forum, posting, asking questions, and sharing how your journey is going.
..take care.. tim b