repeatedly press f8 after youve pushed the power button. this will start your pc in safe mode. click the start menu and in the run box type ( msconfig ) only using the letters m,s,c,o,n,f,i,g. then select the startup tab located at the top center of the popup screen. you will then see a list of items with a check mark located next to each of them or just some of them. unchech each one and then hit apply. you will then be prompted to restart your system. let it startup normally. you will get a prompt telling you your system has been changed to a selective startup. just check the box and choose it not to prompt you again. this should allow you to boot up and use your anti virus program to remove the virus threat.
you will no longer see some of the icons in the lower right hand corner of your screen as a result of unchecking those items, but they will still function properly without any issues.
below , i have included a link that will provide you with a w32/blaster worm removal tool. download the program to your desktopp the doublle click the icon to run the tool. this wiull be extremely helpfull if your AV software is out of date or already corrupted by the worm itself. a blaster worm has the potential to completely disable your current AV program, so id for sure try it first as a definate removal result.
if you need any further assistance in helping you with this , please feel free to contact me via [email protected]