Just a thought, not ideal:

I know in Excel and Gnumeric, in the upper left, there is a "name" box. It usually contains the cell you are in "A1". You can type in that box "A1:F1" to select A1, B1, C1, D1, E1, and F1. Don't know if that applies to Thinkfree or Docs to Go, but it might be worth checking.