amazon ec2 hangs while editing text

Hi I am beginner in AWS services. For my rails application , I am using micro and medium instances . One of my instance is micro in that I cannot use any text editor like nano,vim, joe its hangs out while trying to open any text file even its less than 100 kb. While trying to copy files by scp also it stalled. In other instances text editors works well. This is the log file I got while trying to to copy file from EC2 to my local

debug2: channel 0: request exec confirm 1
debug2: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug2: channel 0: rcvd adjust 2097152
debug2: channel_input_status_confirm: type 99 id 0
debug2: exec request accepted on channel 0
debug2: channel 0: rcvd ext data 52
Sending file modes: C0664 103506 home_controller.rb
debug2: channel 0: written 52 to efd 6
Sink: C0664 103506 home_controller.rb
home_controller.rb                              0%    0     0.0KB/s - stalled 

help me ...