You might try to clear the system cache, that might release just enough memory:
Turn off phone
Remove the battery and reinsert.
Hold down the Home and Volume Up keys
Press and hold the Power button while still holding the other keys.
As soon as you see the Samsung logo, release all keys/buttons.
Press on the Volume Down to scroll down to Wipe Cache Partition.
Press the Power button to select it.
Press the Volume down button to highlight "Yes" and press the Power Button to select it.
Wait for a few minutes for the phone to clear the data.
Then press the Power button to select reboot system now.
Wait for your phone to reboot.
If that doesn't work, try another computer with the software assistant installed.
If you can backup anything (you dont say the phone is un-usable) do so and factory reset the phone.
If that doesn't work, perhaps you still have an extended warranty and can get a replacement because it sounds like the phone may be potentially corrupted.