Email - Make sure the mail app is completely closed by double pressing the Home button, pressing and holding an icon on the bar tha appears on the bottom of the screen until a minus sign appears on the icons. Then press the minus sign on the mail app. Reboot your iPad by pressing and holding both the Home and Sleep/Wake buttons at the same time until the Apple symbol appears.
Music - Windows Media file as far as I know aren't compatible with iTunes. You can rip CDs directly into iTunes though.
Try going into Settings > Mail, Contacts, Calendars. Then select the account on the right-hand side of that screen, select Account, then Advanced, Deleted Mailbox, and under On The Server tap the 'Trash' folder so that it gets a tick against it - then come out of that series of popups by tapping on the relevant buttons at the top of them and then see if you can delete emails.
Have you got the latest version of iTunes installed on your computer (and I assume that you have your music in iTunes and are trying to sync via it) ?
Syncing music to the iPad's Music app : http://support.apple.com/kb/HT1351
It uses the file sharing section at the bottom of the Apps tab when connected to your computer's iTunes.
There is an online manual for the app here : http://www.goodreader.com/gr-man.html
Syncing documents to it : http://www.goodreader.com/gr-man-howto.html#transfer
Copying documents via iTunes : http://www.goodreader.com/gr-man-tr-usb.html
Complete guide to using iOS 6
You can download a complete iOS 5 iPad User Guide (Apple has not yet published an iOS 6 Users Guide for the iPad) here: http://manuals.info.apple.com/en/ipad_user_guide.pdf
Also, Good Instructions http://www.tcgeeks.com/how-to-use-ipad-2/
Apple - iPad - Guided Tours
Apple iPad Guided Tours - Watch the videos see all the amazing iPad apps in action. Learn how to use FaceTime, Mail, Safari, Videos, Maps, iBooks, App Store, and more.
How to - Articles & User Guides & Tutorials
iPad How-Tos http://ipod.about.com/lr/ipad_how-tos/903396/1/
You can download this guide to your iPad.
iPad User Guide for iOS 5