Hello, my name is Dan.
I will do my best to help you, the only stupid question is the unasked one.
Ok, I see what you have. Safari has unexpectedly quit or something like.
Did you prepare for the Lion upgrade? I mean did you repair permissions, back it all up, run the UNIX routines, etc? Probably not, many don't because it isn't made clear to do so. Then things like this happen.
Not to worry though, it is all fixable except the backup part, that, if not done, can't be fixed.
This PDF explains how and why to repair permissions.
I also recommend a SafeBoot, this is done the UNIX routines to clear cobwebs.
To do a Safe Boot, restart and before the first chime press and hold the 'Shift' key.
Wait until you see the Apple logo and the spinning gear appear, then let go.
It can take as long as 20 minutes to load, so please be patient.
When the login screen appears it will say in red on the login window 'SafeBoot'.
Now login and give it a few more minutes to finish loading.
Try doing whatever it was it was giving you the problem. If it works then probably the problem is solved, so restart normally.
If the problem persists then restart normally also, other fixes will need to be done.
Do those and see what happens, then get back to me please.