I consider myself a home theater novice, but if I had $10,000 to spend on home theater equipment, I would use at least half of that money to purchase a DLP front projector or used CRT projector AND a high quality screen (I am learning alot about home theater by searching the archives at http://www.avsforum.com).
Your home theater would be "driven" by the large and often film-like picture that these projectors can provide and then be complemented by a moderately priced home theater audio system (e.g. DVD player, AV reciever, satellite / subwoofer speaker system) that probably won't shake the room but can cleanly and UNOBTRUSIVELY reproduce the soundtrack of the movie you are watching.
My preliminary research suggests that there are alot of high quality DLP projectors and used CRT projectors available at street prices from $2000 - $5000 (I personally have found that the reviews and educational articles by Evan Powell at http://www.projectorcentral.com to be very educational and informative).
And that still leaves over $5000 for the audio components. If her system will be dedicated primarily to home theater and not asked to reproduce very high quality 2 channel audio, she should be able to put together a very satisfying system (even new) for that amount of money.
Finally, if your friend is relatively new to audio, I would suggest that she audition a lot of COMPLETE audio systems (I would recommend the same for projector / screen combinations) with source material that she truly enjoys. This will help her define exactly what her audio and video preferences are. Purchasing a complete audio system new from a dealer that she trusts, is informative, and provides fair package deal pricing may actually may actually provide her with more long term "value" because she hopefully won't be quickly drawn into the upgrade cycle that many audiophiles (myself included) found ourselves in when putting together high quality, used components that didnt' synergize well together or really didn't reflect our personal preferences.
Hope this helps!