Please help beginner with her iPhone 3G

Dear community!
first i want to say, im not really a crack in computer stuff and espacally when its in englisch So, please answer in simple, easy words..
1. my phone does not ring when i get a call... alarms do work... all settings are loud... whats wrong?
2. how can i send mms? i have 3.1.2 and i read on apple.com, that it is possible to write mms with the iPhone 3G... But how?
3. with my pc (windows vista)i cant restore my iPhone... Always says that drivers are not available... with my ipod touch, it works (iTunes 9,?). i have to do this then with an mac book... but this cant be the solution...
would be pleased if you can help me!
Sarah
sony vaio Windows Vista