I have Skype on my droid.... but to use it I need to have a signal and have the "network" turned on. I think I've used it once or twice to speak with a buddy in Argentina on Skype..... no long distance charges at all.... very nice, but I have to be near my wifi or have the network on.
At my house my cell service sux too.... but I have wi-fi and a network cell hotspot so I have wireless internet. The cell hotspot is supposed to act like a mini cell tower...... yeah.... not exactly, but if I'm setting within 10 feet or so, I can generally make a call.....and with the wireless network (data) I can access the internet easily. I have unlimited data.....old plan.... so I don't care about data usage...calling is another issue but I've never run over, and that's with 2 girls on it but for teens.....phone calls are so yesterday.... unlimited texting rules...
But with out the cell service, there is no phone or internet connectivity. So internet calling won't help.