10.6.8 upgrade problems

I've been VERY happy with my MBP since I bought it a year ago. However after the 10.6.8 update yesterday I have had the following problems:

1. Startup time VERY slow - 30 sec to login screen, then 7 minutes after user/pass entered to log in

2. Network Printer stopped working - after clicking print button, print job appears to hang, and print options shows printer as Paused. Unpausing does not correct this (and doc does not go to print)

3. Firefox hangs - Firefox upgraded to 5.0 at the same time, and now hangs system using 100 %cpu. It can take several minutes to free system again. I supect this may be due to add-on incompatibility but yet to figure out if actually the case.

4. Log out slow - can take 1-2 minutes to log out.

5. Accessing network shared folders is VERY slow.

Specs of my system are 2.66Ghz dual core i7 MacBookPro6,2 with 8GB 1067 DDR3

Is is connected to SBS2008 network/active Directory and has not had problems in the past. Interestingly, if I change network to be tethered to my iphone the Firefox and slow network issues vanish.

Screenshot of Console error message relating to "class ... implemented in both ... One of the two will be used. Which one is undefined". I've no idea what this is, or what it relates to, and would appreciate help with troubleshooting the slow login/out issues and printer problems. Firefox seems to be behaving atm after removing some add-ons.

Thanks in anticipation of your help

James