1. mid-June through mid-August is prime time but all depends on how the summer goes.
2. I climbed without would expect it's 50/50
3. The guide services have good lists to start with Alpine Ascents RMI AAI
4. Good crampon conditions. When the snow is hard you are more effecient. Also the snow bridges and snow surrrounding crevasses is more stable. Rock/Ice fall is more limited due to stable conditions as well. As things start to heat up stuff breaks apart.
5. Yup. Lots of peaks have them.
6. Wikipedia Link
7. Good Article
8. No. Not to attain a climbing pass. But is highly recommended you have confident glacier travel experience. Including using an ice axe, team rope travel, routefinding, self rescue and crevasse rescue techniques amongs others. Many of the guide services offer courses. Then just good 'ol experience comes into play.
9. Not being prepared covers most of them. Including many I have made.
10. I tried but her agent blew me off