I think you need to fix your computer. I have never seen the desktop software crash on a healthy system. You should make sure you don't have any virus's (http://housecall.trendmicro.com)
, make sure you don't have any spyware/malware (MS Antispyware/Spybot/BHODemon), make sure your apps are up to date (Windows Update/Office Update), make sure you have the newest desktop software (www.blackberry.com)
. If these don't fix your machine, you should reload your OS.
Getting back to your questions...
#1. I assume you meant 'two' mailbox's... no.
#2. You need to do nothing, except signup and give your credit card info.
#3. Do some research... find out what providers are out there, and see if you can get some third party references about them... It just so happens that there may be a whole FAQ here and a few threads about the various BES hosting providers available. Why don't you try and do a search, I know it's tough to figure out, but I'm sure you can do it.