Droped Calls and Poor Service.

My roommates each have an iPhone (bleagh!) and they are both experiencing the same problems. I am trying to solve these problems for them as I am more tech orientated than both of them combined, but my knowledge doesn't extend to apple products for personal reasons.

Here is what is going on.

Both of them when they are at home, cannot get a signal to save their lives. If that were truly the case, they would be pretty screwed. They are constantly borrowing my Nokia (T Mobile) which gets great reception.

One has an older version and it works fine outside of the end of the block where we live.
The other one has a 3g and her signal pretty much sucks everywhere. Her texts seem to take forever to go through also.
And we live in a 'good' zone, according to at&t.

I guess what I need to know is, first: how do I find out exactly which models they have, which FW, etc. All the pertinent stuff. That would be a good start.
Second: has anyone else experienced any problems with at&t or apple regarding their iphones?

The one with the older phone updated his today and it did absolutely nothing. After that he took off and drove to the at&t store and they pretty much said they couldn't do anything.

Normally I would sit back and say 'Haw Haw, but I generally feel bad for them and want to help.

My questions: could my wi-fi/router be causing this? Is the power station across the street be causing any of this? Should I run a spectrum analyzer? Will that help anything?

Thanks in advance.
Shawn.