If neither phone was plugged in at the time of the surge, the surge cannot have affected them.
From the User Guide (http://manuals.info.apple.com/en_US/iPhone_iOS4_User_Guide.pdf):
Restarting and Resetting iPhone
If something isn’t working right, try restarting iPhone, force quitting an app, or
Restart iPhone: Press and hold the On/Off Sleep/Wake button until the red slider
appears. Slide your finger across the slider to turn off iPhone. To turn iPhone back on,
press and hold the On/Off Sleep/Wake button until the Apple logo appears.
If you can’t turn off iPhone or if the problem continues, you may need to reset iPhone.
A reset should be done only if turning iPhone off and on doesn’t resolve the problem.
Force quit an app: Press and hold the On/Off Sleep/Wake button for a few seconds
until a red slider appears, then press and hold the Home button until the app quits.
You can also remove an app from the recents list to force it to quit. See “Opening and
Switching Apps” on page 29.
Reset iPhone: Press and hold the On/Off Sleep/Wake button and the Home