figure out what program they are associated with. either right click and click about, or help, or info.
once you figure out which program it is with. go into control panel>add or remove programs> find the program> and then click remove/modify. be careful to not remove a useful or critical program such as your video card driver, you sound card driver or your anti-virus.
if it is not in the add, remove program window. then it is most likely spyware or another form of malware. you will need to get a spyware/malware remover. I never got any of those because I'm careful but you could google it. also, beware when downloading these because they could be a virus also. download only from trusted sites.
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click start >then run type msconfig in the box and press enter
select the startup tab and take the ticks out of the boxes that correspond with the icons/programs.
be careful when doing this, it may alter the way your computer starts up but could also speedup startup process.