ok, so i have a little difficulty, i and other users on our shared computer don't use it well, and often corrupt windows! so we have to format it again, and i format it always. so after each format, i need to install all programs again. what other programs setup should i keep? can you also give a little description(if possible) for each and tell whether its freeware or costs to get a full version?
and, also can you recommend an antivirus? other people on our computer complain that its too slow because of antivirus, so can you tell one which doesn't slow down pc?
thanks in advance!

Well the anitviruses that I ve had in the past are Macafee , kaspersky, Enod they are really good and they don't slow down your pc.

what else would you need other than your browser

other than my browser? i need something to play songs, take videos(for which i am using fraps), antivirus, a download manager(for which i am using idm), a software to watch videos, etc. i mean all those softwares that i may use. but i already made a list and got some, so i don't need any more help. thanks.
and blackheartwarrior, they all slow down pc. you should use avast free, i tried it and it doesn't slow down pc.

Well, I think u should have good anti-viruses such as Kaspersky, Avast, etc. And Disk Clean-up.