Problems with Windows and Random Crashes

Question

For the past two days I have been having tons of problems, since I finally got around to running the security update (2006-008). I've been having loads of random crashes, most commonly from Safari, Finder and iTunes. Safari crashes usually when I close a window or interact with certain flash things. It also fails to draw the window when I close the second-to-last tab (leaving one tab), giving me a big white square that I have to close. Otherwise, random window elements (such as bookmarks bar, address bar, etc.) will disappear at random, or will be horribly mis-sized.
Finder just quits whenever it wants, I have yet to find a common thread between crashes.
iTunes crashes usually when I play a video, but also sometimes when switching from the store to a playlist, or to the library. It also suffers occasional redraw problems similar to Safari, though not as bad. Garage Band does too.
Here's the output from the last iTunes crash, if it provides any clues:
EXCBADACCESS (0x0001)
KERNINVALIDADDRESS (0x0001) at 0xffffffff
Thread 0 Crashed:
0 GetPatternIdentifier + 211
1 SetPortPat + 103
2 BackPixPat + 42
3 DataEngine::ApplyBrush(TTheme*, short, unsigned char) + 76
4 SetThemeBackground + 836
5 SetThemeWindowBackground + 292
6 NewFeaturesDialog + 202
7 CreateDialog(Rect const*, unsigned char const*, unsigned char, short, OpaqueWindowPtr*, unsigned char, long, char**, ColorTable**, char**, char**, unsigned long, unsigned char, AutoPositionInfo) + 175
8 GetNewDialog + 173
9 0x1000 + 1686314
All of my crashes have been EXCBADACCESS (0x0001) ones.
Please help, as this is a nightmare to deal with.

Answer 1

That error usually comes up as a result of faulty RAM. Did you buy any chance upgrade the RAM in your iMac? If so, verify that the chip is seated properly and that it is supported for your iMac.