iTunes downloads not downloading

When I am on iTunes and try to download anything, whether Safari is activated or not... it will start for 2 seconds then stop. when I click to inquire a box says; problem downloading... unknown error occurred (406). So far, I have only tried to download podcasts and this is really frustrating given what's out there!
I don't know where to start looking to solve this problem. Unfortunately I'm one of those who still have dial-up. ugh. When I am not on iTunes and try to download from other sites it's fine. (just takes years)
Another problem is that Safari sometimes just won't connect anymore and the only way to solve this problem is by rebooting my mac. btw, my internet provider is Opexonline. I rarely have a problem w. them.

I hope someone can help... A.