How Do I Reset / Cancel a "Stuck" Install?

Question

When I Restart my computer, a window pops up saying "Continue the installation?" (Abort) (Yes) then quickly disappears to restart before I can click anything.  I do recall trying to cancel what seemed to be a malicious software install.  How can I get rid of this?
I have an Intel iMac late 2009 with OS X 10.9.5.  I have run the latest Onyx utility for Mavericks to clean out System and User cache, rebuilt LaunchServices and dyld's shared cache, deleted temporary files as well as Repaired Permissions, but the problem persists.  So far, this is only causing me annoyance and concern - everything seems to still be working OK.

Answer 1

I was able to resolve my own problem... with a LOT of investigation.
In Activity Monitor, there was a process called Installer.  When I opened it and clicked the Open Files and Ports tab, I found references to com.genieoinnovation.Installer (see full listing below) which I found odd.  So I did some Google research and found that Genieo (and InstallMac, Omnibar, and Spigot) is malicious adware... a virus almost.  I ran MacScan2 (with the current updates of course), but it did not detect it.  I then ran ClamXav, and it found 2 files it quarantined: Reset Search.app and Completer.app - both with Infection Name OSX.Adware.Omnibar.  I deleted them, based on what I read from my Google results.  I used Onyx to Show hidden files and folders and used Spotlight to find anything else with "omnibar" and deleted it.  I then went through the list below and deleted anything related to "genieo" and "installmac" and "spigot" as well.
/Users/Myron/Library/Application Support/com.genieoinnovation.Installer/Completer.app/Contents/MacOS/Installer
/System/Library/ColorSync/Profiles/Generic Gray Gamma 2.2 Profile.icc
/System/Library/ColorSync/Profiles/sRGB Profile.icc
/Users/Myron/Library/Caches/com.genieoinnovation.Installer/Cache.db-shm
/private/var/db/mds/messages/se_SecurityMessages
/usr/share/icu/icudt51l.dat
/private/var/folders/tv/hnmz5_r55fxbwtktmb9byvnr0000gp/C/com.apple.IntlDataCache .le.kbdx
/private/var/folders/tv/hnmz5_r55fxbwtktmb9byvnr0000gp/C/com.apple.LaunchService s-044502.csstore
/System/Library/PrivateFrameworks/CoreUI.framework/Versions/A/Resources/SArtFile .bin
/System/Library/Keyboard Layouts/AppleKeyboardLayouts.bundle/Contents/Resources/AppleKeyboardLayouts-L.d at
/System/Library/Fonts/Times.dfont
/usr/lib/dyld
/private/var/db/dyld/dyld_shared_cache_x86_64
/dev/null
/dev/null
/dev/null
count=2, state=0x2
/Users/Myron/Library/Caches/com.genieoinnovation.Installer/Cache.db
/Users/Myron/Library/Caches/com.genieoinnovation.Installer/Cache.db
/Users/Myron/Library/Caches/com.genieoinnovation.Installer/Cache.db-wal
/Users/Myron/Library/Caches/com.genieoinnovation.Installer/Cache.db-shm
/Users/Myron/Library/Caches/com.genieoinnovation.Installer/Cache.db-wal
FNetwork.defaultStorageSession
->0xc4ba1ef855ef283f
->0xc4ba1ef855ef2907
I restarted, and everything was fine after that.