There is a utility called "HijackThis", here's the nfo and the web site
* HijackThis v1.97 *
Written by Merijn -
merijn@spywareinfo.com
http://www.spywareinfo.com/~merijn/files/hijackthis.zip
http://www.spywareinfo.com/~merijn/index.html
See below version history for short info on hijack sections.
* Version history *
[v1.96]
* Lots of bugfixes and small enhancements! Among others:
* Fix for Japanese IE toolbars
* Fix for searchwww.com fake CLSID trick in IE toolbars and BHO's
* O19 (user stylesheet) now only checks for known bad filenames
* Attributes on Hosts file will now be restored when scanning/fixing/restoring it.
* Added several files to the LSP whitelist
* Fixed some issues with incorrectly re-encrypting data, making R0/R1 go undetected until a restart
* All sites in the Trusted Zone are now shown, with the exception of those on the nonstandard but safe domain list
[v1.95]
* Added a new regval to check for from Whazit hijack (Start Page_bak).
* Excluded IE logo change tweak from toolbar detection (BrandBitmap and SmBrandBitmap).
* New in logfile: Running processes at time of scan.
* Checkmarks for running StartupList with /full and /complete in HijackThis UI.
* New O19 method to check for Datanotary hijack of user stylesheet.
* Google.com IP added to whitelist for Hosts file check.
[v1.94]
* Fixed a bug in the Check for Updates function that could cause corrupt downloads on certain systems.
* Fixed a bug in enumeration of toolbars (Lop toolbars are now listed!).
* Added imon.dll, drwhook.dll and wspirda.dll to LSP safelist.
* Fixed a bug where DPF could not be deleted.
* Fixed a stupid bug in enumeration of autostarting shortcuts.
* Fixed info on Netscape 6/7 and Mozilla saying '%shitbrowser%' (oops).
* Fixed bug where logfile would not auto-open on systems that don't have .log filetype registered.
* Added support for backing up F0 and F1 items (d'oh!).
[v1.93]
* Added mclsp.dll (McAfee), WPS.DLL (Sygate Firewall), zklspr.dll (Zero Knowledge) and mxavlsp.dll (OnTrack) to LSP safelist.
* Fixed a bug in LSP routine for Win95.
* Made taborder nicer.
* Fixed a bug in backup/restore of IE plugins.
* Added UltimateSearch hijack in O17 method (I think).
* Fixed a bug with detecting/removing BHO's disabled by BHODemon.
* Also fixed a bug in StartupList (now version 1.52.1).
[v1.92]
* Fixed two stupid bugs in backup restore function.
* Added DiamondCS file to LSP files safelist.
* Added a few more items to the protocol safelist.
* Log is now opened immediately after saving.
* Removed rd.yahoo.com from NSBSD list (spammers are starting to use this, no doubt spyware authors will follow).
* Updated integrated StartupList to v1.52.
* In light of SpywareNuker/BPS Spyware Remover, any strings relevant to reverse-engineers are now encrypted.
* Rudimentary proxy support for the Check for Updates function.
[v1.91]
* Added rd.yahoo.com to the Nonstandard But Safe Domains list.
* Added 8 new protocols to the protocol check safelist, as well as showing the file that handles the protocol in the log (O18).
* Added listing of programs/links in Startup folders (O4).
* Fixed 'Check for Update' not detecting new versions.
[v1.9]
* Added check for Lop.com 'Domain' hijack (O17).
* Bugfix in URLSearchHook (R3) fix.
* Improved O1 (Hosts file) check.
* Rewrote code to delete BHO's, fixing a really nasty bug with orphaned BHO keys.
* Added AutoConfigURL and proxyserver checks (R1).
* IE Extensions (Button/Tools menuitem) in HKEY_CURRENT_USER are now also detected.
* Added check for extra protocols (O18).
[v1.81]
* Added 'ignore non-standard but safe domains' option.
* Improved Winsock LSP hijackers detection.
* Integrated StartupList updated to v1.4.
[v1.8]
* Fixed a few bugs.
* Adds detecting of free.aol.com in Trusted Zone.
* Adds checking of URLSearchHooks key, which should have only one value.
* Adds listing/deleting of Download Program Files.
* Integrated StartupList into the new 'Misc Tools' section of the Config screen!
[v1.71]
* Improves detecting of O6.
* Some internal changes/improvements.
[v1.7]
* Adds backup function! Yay!
* Added check for default URL prefix
* Added check for changing of IERESET.INF
* Added check for changing of Netscape/Mozilla homepage and default search engine.
[v1.61]
* Fixes Runtime Error when Hosts file is empty.
[v1.6]
* Added enumerating of MSIE plugins
* Added check for extra options in 'Advanced' tab of 'Internet Options'.
[v1.5]
* Adds 'Uninstall & Exit' and 'Check for update online' functions.
* Expands enumeration of autoloading Registry entries (now also scans for .vbs, .js, .dll, rundll32 and service)
[v1.4]
* Adds repairing of broken Internet access (aka Winsock or LSP fix) by New.Net/WebHancer
* A few bugfixes/enhancements
[v1.3]
* Adds detecting of extra MSIE context menu items
* Added detecting of extra 'Tools' menu items and extra buttons
* Added 'Confirm deleting/ignoring items' checkbox
[v1.2]
* Adds 'Ignorelist' and 'Info' functions
[v1.1]
* Supports BHO's, some default URL changes
[v1.0]
* Original release
A good thing to do after version updates is clear your Ignore list and re-add them, as the format of detected items sometimes changes.
The different sections of hijacking possibilities have been separated into these groups:
R - Registry, StartPage/SearchPage changes
R0 - Changed registry value
R1 - Created registry value
R2 - Created registry key
R3 - Created extra registry value where only one should be
F - IniFiles, autoloading entries
F0 - Changed inifile value
F1 - Created inifile value
N - Netscape/Mozilla StartPage/SearchPage changes
N1 - Change in prefs.js of Netscape 4.x
N2 - Change in prefs.js of Netscape 6
N3 - Change in prefs.js of Netscape 7
N4 - Change in prefs.js of Mozilla
O - Other, several sections which represent:
O1 - Hijack of auto.search.msn.com with Hosts file
O2 - Enumeration of existing MSIE BHO's
O3 - Enumeration of existing MSIE toolbars
O4 - Enumeration of suspicious autoloading Registry entries
O5 - Blocking of loading Internet Options in Control Panel
O6 - Disabling of 'Internet Options' Main tab with Policies
O7 - Disabling of Regedit with Policies
O8 - Extra MSIE context menu items
O9 - Extra 'Tools' menuitems and buttons
O10 - Breaking of Internet access by New.Net or WebHancer
O11 - Extra options in MSIE 'Advanced' settings tab
O12 - MSIE plugins for file extensions or MIME types
O13 - Hijack of default URL prefixes
O14 - Changing of IERESET.INF
O15 - Trusted Zone Autoadd
O16 - Download Program Files item
O17 - Domain hijack
O18 - Enumeration of existing protocols
O19 - User stylesheet hijack
You can get more detailed information about an item by selecting it from the list of found items or highlighting the relevant line above, and clicking 'Info on selected item'.
EDIT: Damn, thats a BIG post :P