sounds like you will do ok staying in Ouray. I would check out the hot springs there!

To add one thing to what has been said. Take rolaids/antacid. 3-4 tablets every 4-6 hours. Saw a doctors article on altitude that said that studies showed this helped also. I take 3 three times daily for the first several days.

Also, I wouldn' t take the aspirin before hand. You don' t want to bleed if you happen to cut yourself. Have not seen any medical source that recommended this or not, so I can' t reliable badmouth it, but what I have always done is take either aspirin or ibuprophen when I get there for headaches and muscle sorness. I would recommned ibprophen.

Water has been mentioned, but can' t be emphasized enough

Also, listen to eveyone on the caffeine and alcohol. It makes a big difference to avoid it for a few days before and after you arrive. I usually start taking either in small amounts 4-5 days after arrival. Can usually tolerate it by then.