Would moving the Finder preference file to your Desktop and starting help? If it's a Finder issue perhaps forcing Finder defaults may help?
Quick question, how did you install Lion? I'm asking as some people installed it over Snow Leopard and are running into issues. You can install it fresh by burning the dmg in Lion(DP1 or 2, doesn't matter but DP2 will be best)/Contents/SharedSupport/
InstallESD.dmg to DVD or USB:
Creating a bootable OS X 10.7 Lion disc (Update: …and USB stick)
I booted up with a fresh SSD and installed fresh, and it fixed a lot of issues (such as not being able to delete any app's in Launchpad and some app's that were not working in DP2 update 2 work well).
Hope this helps! I'm gonna post a thread with this info as well in case others want to know.