First see if you can access the language settings menu on the player -- maybe it's flipped to Hebrew -- though I've never come across a player which offered that option so you may actually be seeing random characters that just resemble Hebrew.
Check any CD which came with the player for a copy of the firmware and instructions on how to reload it.
Philips' home site has quite a good support section on MP3 and it may contain a newer firmware download for your model.
You might lose any music on the player if you reflash it.
Note that it is not a good idea to format MP3 players using Windows. Always use the player's inbuilt format facility.