1. You'll need a gamil account to be a master account for the device. Your market credentials and GTalk login are tied to this account. There is a dedicated app for this that uses push technology for instant email availibility.
Your other Gmail and Pop accounts can either be forwarded to this account (done on gmail.com) for push, or set up on the Htc mail client. The Yahoo account can be used as is as an IMAP account, or by paying the annual fee to Yahoo can be used as a POP account.
What I would do -
Use MY (I really mean YOUR lol) Gmail account as the "master" account. I would configure my Gmail to poll and collect my POP3 accounts, and push them to the phone. Set all this up on gmail.com from your PC. The emails come in labeled from which account they are from, and when you reply to them it replies through THAT account and not Gmail (if you prefer).
Use the Htc Mail client to set up your Yahoo account. Set it up as an IMAP account. Many tutorials about this on the web. Search iPhone Yahoo IMAP setup.
Use the Htc Mail account to set up the other (I assume your wife's) Gmail account.
2. There is a section in the included user guide that covers this very well, step by step. Very basic and easy to understand.
3. Log into your gmail account (the "master" acct) via gmail.com, go to your calendar and set it to show and share with your wife's calendar. The calendar on the phone will then show your calendar as well as your wifes, using a seperate color for each accounts entries.
4. Piece of cake. Any function I have been able to think of asking for has either been built into the OS or is readily available from the market. Follo the droid forums here, as they have asked just about any question one could have
One thing you need to do -
There is currently a bug in the Htc Messaging (your SMS and MMS) app that will keep the phone awake and drasticly shorten battery life. An easy work around has been found, and Sprint/Htc have promised that this is easily fixable and will soon release a patch. In the meantime -
Download Handcent SMS or ChompSMS from the market. Both have strengths and weaknesses, personally I recommend Handcent.
Go through the settings and set it up how you would like it. Both are very customizable as well.
Open the stock Htc messaging app, and turn off all notifications.
Select a contact and send an SMS message. the pop up will ask you which service you would like to use. Make sure "use by default" is checked then select Handcent (or ChompSMS). Send the text, and recieve one back. Make sure you open the rec'd message via Handcent (Chomp).
Restart your phone (hold power off button 3 secs. then pick power off, then hit power button again).
After phone restarts, do something. Anything. Check your mail, twitter whatever. Then manually put phone to sleep by tapping the power button, and wake it up again usng the menu button.
AS long as you do not use the stock messaging app this should fix the sleeping issue. I'm sure once Sprint/Htc has a true fix we will all be talking about it, but this works fine in the meantime, and both Handcent and Chomp are great apps that I'll likely use anyway.
Hope this helps. Of course, any specific questions you have be sure to ask. We're all here to help. Enjoy your phone!
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