You shouldn't be seeing adchoices,
then reset it to default (it will pick up your existing preferences, unless you removed those previously when uninstalling the first time)
Download the Avast Browser Cleanup tool from here:http://files.avast.com/files/tools/avast-browser-cleanup.exe
Double-click on the downloaded file to execute the program.
It scans the computer for adware and other unwanted add-ons or extensions.
Remove the identified items and restart the browser.
reset all the browsers back to default:
Open Internet Explorer, click on the gear icon at the top (far right), then click again on Internet Options.
In the Internet Options dialog box, click on the Advanced tab, then click on the Reset button.
Reset Internet Explorer
In the Reset Internet Explorer settings section, check the Delete personal settings box, then click on Reset Internet Explorer back to its default settings
When Internet Explorer finishes resetting, click Close in the confirmation dialogue box and then click OK.
Close Internet Explorer.
At the top of the Firefox window, click the Firefox button, go over to the Help sub-menu and select Troubleshooting Information.
Click the Reset Firefox button in the upper-right corner of the Troubleshooting Information page.
To continue, click Reset Firefox in the confirmation window that opens.
Firefox will close and be reset. When it’s done, a window will list the information that was imported. Click Finish
enter the following into the Chrome address bar:
• and at the bottom click on "Advanced Settings"
• At the very bottom of the page click on "Reset Browser Settings"
Instructions on how to backup your Favourites/Bookmarks and other data can be found below.
Backup Internet Explorer Bookmarkshttp://www.wikihow.com/Back-Up-Favorites-in-Internet-Explorer
Backup Firefox Bookmarkshttps://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer
Backup Chrome Bookmarkshttp://www.wikihow.com/Export-Bookmarks-from-Chrome