Question from a noob

[Outrun]

Hi, we currently use Freeview (im in the uk), so i have never used Satallite TV before (planning to get Freesat), so please forgive my possibly obvious questions.

1: I know that you can record more than one channel from a single TV cable (my current freeview box can record two shows at the same time), what i ideally want is to record 4 HDTV channels Simultaneously from a single ariel cable, i would like to know if that that is possible, also would i need the TBS6922, 6925, or 6985 if this is possible. i read about the 6985 - it mentioned transponders or something, i know very little about this so keep your answers simple is possible.

2: Can a single satallite dish provide signals to two different Satallite TV boxes? i plan to buy one of the ones mentioned for my desktop pc, but my mum is getting a FreeSat PVR for the living room (we live in the same house), would we need to get another satallite dishe for that to work?

3: are there any other points i would need to know - from a noob perspective?

Note - i have the Intel 3570k CPU so i know i can record that many channels easily.