A bit more information ....
This freelotto banner thing may not be caused by FREELOTTO.COM. According to their website other spurious websites or spyware might refer you to freelotto. You also had an advert or you were redirected to a casino site, which would suggest you have a BHO. This link has some useful advice on how to get rid of an unwanted BHO:
http://www.pcflank.com/art36.htmIf you cannot download a program to get rid of it then you could edit your registry and get rid of it that way. I would suggest you open NotePad first so that you can paste those long GUIDs somewhere. Right click a entry in your BHO section and select
Copy Key Name and then paste it into NotePad like so:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects\{02478D38-C3F9-4EFB-9B51-7695ECA05670}
Once you have copied them all, copy just the curly braces part and click on
Edit and then
Search on the menu bar and then copy the curly braces number into the search box and click Find Next. There may be several entries for one GUID, so keep searching until you arrive back at the first one again.
The article mentions that there is probably a .dll file out there that is being used to redirect your browser or causing banner ads to be displayed across the screen. When you find the offending BHO make a note of the file it points to e.g.:
C:\Windows\System32\bannerads.dll
Delete the BHO and then delete the .dll file above.