Just after booting (when attempting to use dhcp) use dmesg to see the kernel messages, it may be worth comparing this with the same output from your statically set IP address.
If you want to save the dmesg output for later, you could do something like:
dmesg > ~/dmesg-dhcp.log
Note, contrary to what an earlier poster said, always go for a reinstall as a very last measure - almost everything can be fixed that you can break in Linux.