I am in Trouble…

I run Cyber cafe in India, since it cyber cafe
different types of customer visit my cafe.
customers are 3 types
1) chatters
2) send/receive mails and genuine downloads.
3) XXX rates sites visiters.

Its local pc,

they visit xxx,Adults sites, save dirty images into my pc. any where in C:\ Drive or D:\drive.

download clippings into my pc and save them for future watching. any where in C:\ Drive or D:\drive.

i do clear all images and delete clippings..
but every hour i cant do it.

is there any software when i restart my pc every thig which is downladed by customer shld get deleted except ms-office files and acrobat files.

i have windows XP professional into my PC.