Hello and welcome:
90CM should be OK for your area. I am in NYC area and have the 90 and it performs well.
A Dish network receiver cannot be used for FTA as it will oly receive their programming. A proper FTA receiver is the way to go and
Sadoun has several bundles on his site that will work for FTA.
Most Russian channels are on IA-5 satellite at 97 degrees w latitude. The rule of thumb is if it has 4 digits for the frequency (4189 H) that would denote
C band and you would need a dish 6-10 feet for proper reception of that. If the frequency is 5 digits (11741V) that is Ku band and a dish 90CM up will be sufficient for that.
C-band is far from "dead". In fact, the most intresting programming can be found on C band but in some cases requires a diffrent type of receiver, like a 4DTV (DSR-922) because the transmission is in Digicipher2 format and the FTA receivers use DVB format.
Blind Scanning is done when you don't have a chart of channels form Lyngsat or Satcodx and want to find "wild" feeds on a transponder. A blind scan is a very useful feature to have and most receivers have the capability. A blind scan will search for "active" transponders on a satellite first and then download the channel list from each transponder and seperate radio from TV. I did a blind scan during the November elections and found a ton of feed channels.
Hope this information helps and again welcome.