There are many way to be got at. so.
there are many ways to protect your self.
1. As you said several addresses for personal mail/ for business mail/ just for surfing.
Easier still is this way.
Go to Start/right click on the E-mail Client[OE/Thunderbird what ever] and click on remove from list.
This means when you fire up your computer the E Mail client does not start up.
Now when next you go on line go to Your ISP home page log on and go to your mail box. Read your mail there.
Delete what you do not want. you could reply to some from there even.
Then when satisfied log off and fire up the E-mail program
Only the mail you want will then come in
Long Winded ?
Not really you wont be deleting a load of stuff you do not want from your inbox.
You won't be getting infected stuff.