Hey, Nomad! Welcome to the club.
1. What is the best way to handle dice rolls? I have been in games that handled this in a variety of ways. What would you recommend? Why?
Advice: I've used the Inn's die roller. It can email the player directly if you plug the email in. More recently, I've found roll20.net to be the best solution. Their die roller is pretty comprehensive and stores the rolls in the chat for reference. Plus, you can tie them into the character sheets and invite the players to roll bringing them into the game more.
2. I've seen people having trouble posting pictures. But I also think this got updated recently. Is there anything I need to know about this?
Advice: That has been resolved. Just plug a URL into the "Add picture" feature when posting and you're good.
3. How many threads can you have for one game? Most seem to have a game thread, a Q&A thread, and frequently a recruitment thread that later goes dormant for obvious reasons. Is it easiest to just post character sheets at the top of the Q&A thread?
Advice: Every new thread adds the potential for confusion, so I usually keep it to the Recruiting, Q&A, and Game, but I know that Alacrity has done a Character thread as well. It really is a matter of preference.
4. I've seen many GMs reserve the top 10 or so slots of the Q&A thread. Are there specific things you do with these or are they 'just in case' slots?
Advice: These are reserved for games where you need to introduce additional things to the players that will have import such as world structure, adventure information, rules, etc.
Additional Advice: I also keep the character sheets on Google Drive and share them with the players so they can edit them and check them as they need to. In addition, I've taken to adding the character sheets to roll20.net so their stats and skills can be tied right into the die roller and I can use the mapping tools.