Browser defender shows Box.net as a safe site but like Craigs list you need to be aware of what you're DL as there are many files from many sources. I don't think Box.net filters at all.
No script need to be learned. The first time I used it I did not like it at all. that's cause I didn't know how to use it. Depending on the site you right click on the round S. At the bottom you'll see the basic web site address. This can usually be allowed. Once you allow the basic site things should load fine. If not look at that list again and see what may be able to be allowed. The whole point is some sights can have as may as 20 different scripts running 18 of which you don't need as they run in the background. This is were 3rd party hackers get in and alter this script to something malicious. Go to the PG home page and you'll see that there are two entries:
1. www.PGMusic.com
2. googleappis
Pretty safe to allow both however the page is usable without the googleapis.
Once you allow something at one site it'll be allowed at all sites.

John
ESI Gigaport HD+
Lenovo Turion II /4 Gig Ram/ Win7x64 be
15.6" Monitor
"The only Band is a Real Band"
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