I have searched this (and several other forums) for a solution and haven’t found even the problem being presented yet…
I will however try my best to fully explain what I’m doing and what Blender is doing in order that someone may happen to know a solution to this issue…
Where to start - hmm
My computer is fairly new - AMD Athlon 64 2700+ with 640MB DDR (available after vid card), nVidia 6100 (shared memory of 128)
I am running Mandrava ONE 2008 (don’t ask me all the technical version numbers on this as I don’t know - but it is THE LATEST stable version) 
Blender 2.45 using Python 2.5(same issue has occured on 2.43 using Python 2.4)
The issue - I have Blender divided into 4 view ports - top (top left), front (bottom left), camera (top right), and side (bottom right), with tool bars at bottom and user thingy at top (the one with ADD on it)
I’ll use an example of using the front view port (although it happens in any viewport) …
I select a group or line of verts and then hit ‘s’ or ‘e’ or click the move arrow and all of the vertices I have selected move across the viewport to the edge of the view or to another part of the model… they do move randomly across… they move scattered (all directions), the however do not do the thing that I was trying to do…
I hope someone has some idea of how to fix this… I completely changed versions of Linux trying to fix this - tried an older version of Blender and Python, nothing seems to work to fix this…
(If this is not in the correct place - just move it - I’m too old to be preached at over a misplaced post.)