Computer starting to get clumsy

[oxymoron]

Hi this is my first post here. I will try to be as detailed as possible, if you guys need more info Pls PM me or reply.

Before i explain my information i must tell you the past. about 1 week ago i did a trend micro scan and it told me 3 malwares found TROJ_DLOADER.OZ ,
ADWARE_FASTERXP , HKTL_IRCKEY.A
I don't have any other info about these... but in the end i got the message Successfully removed.
But the slow speeds still continued.. during the boot up and when opening programs..

Now i followed all the instructions and did all the scans and they are posted..

My pc is still slow.. even thought the scans show everything is clear but i suspect that its not.

Note: After the trend micro scan said "Successfully removed" i upgraded my XP to SP3..

and after the scans i removed MBA-M and installed Windows defender and did a disk defrag using a third party program: Defraggler
i also removed some useless personal files from my documents..

i am not sure how much inaccuracy might have been caused by the things i did above... but if you want me to undo anything or rerun the scans i would be happy to do so Also rememeber that i do not have any system restores because i removed them as instructed.

thank you.

Edit:
oo i forgot my PC specs: http://echeema.googlepages.com/computerspecs.html
only change there would be the: Security(now i use avast free av with COMODO firewall & windows defender), and Operating System(upgraded to SP3)