Win32:NcaseSpy [Trj]

gah.
we just got our computer reformated. when we bought it [a sony vaio], the company, instead of giving us software for windows xp professional, which we PAID for, they gave us windows 98. i prefer 2000. xp is much too buggy for me. we didn’t have the software to reformat, we also didn’t have any clue how to. so we sent it away. this computer programmer who ‘fixed’ our computer installed winxphome. i dislike it immensly… anyhow.
we’ve had our computer back for about two weeks. we had dial-up up until then, recently we switched to directway, an isp type thing through our satellite company, because we live in an incestual amish farming cow breeding town in upstate newyork, and we’ll never have any kind of cable or highspeed internet. ever. and we thought this would be faster. it’s not.
my current problem is this: Win32:NcaseSpy [Trj]. [trojan?]
i’m thinking, because whenever my computer is on, the internet is on [ this bothers me a bit, i felt safer with dial-up] that i need a good firewall. something… free. any suggestions? avast finds this virus/worm everytime i reboot my computer. i deleted it. should i try sending it to the chest? i read the post on this. i did have that 180 thing. i’m going to purchase SpyBlocs 2.0. i hope that helps.