About all I can say is that it sounds like a problem with either the dish, LNB, cable, or modem. <g> Not very helpful I know, but hopefully the tech from Wild Blue will be able to figure it out. It could be something as simple as a bad coax cable or connector, or that the dish aim is just a little off.
I used Hughes Satellite for internet access for several years myself, since cable or DSL was not available in my area at the time. I even moved the dish myself when we moved to our current location several years ago (at the time no other services were immediately available here either, but they were coming). Knowing that I would soon be able to change to cable or DSL, I didn't want to do a permanent install of the dish. So Mike and I built a wooden stand, secured it to the ground with rebar stakes, then manually aimed the dish, ran the cable, and set everything up. The aiming was a bit tricky, you had to be pretty much spot on for it to work properly. Having the dish on the ground was technically illegal, since it contains a microwave transmitter it must be 15 ft. off the ground to prevent the possibility of nuking anybody standing in front of it. Instead of mounting it up high, I merely told people "see that dish, don't stand in front of it if you ever want to have kids". <g> The good thing was that it was easy to clear of ice and snow buildup which would otherwise cause the connection to fail. Anyway, as soon as cable became available I happily jumped ship.
If no other service is available, satellite is OK as a last resort. It is most definitely better than dial-up. <g> Let me know what the solution for your parents turns out to be, Scott.