Have you tried uninstalling SP2 from Add/remove? That is the preferred option.
If that does not work, see
for other methods.
Precision Tower 5810, Quadcore Intel Xeon E5-1630 v3, 3700 MHz
RAM:16 GB PC6400 DDR4 SDRAM 1066MHz
HDD: 2x ATA ST500DM002-1BD14 500GB SATA non RAID
DVD:HL-DT-ST DVD+-RW GTA0N SCSI and PLDS DVD+-RW DH-16AES SCSI
Video: nVIDIA Quadro K4200 PCIe 4GB
Audio: Recon3D PCIe, Altec Lansing ADA995 5.1 speakers
Monitor: Dell E2011H
What you could do is make a copy of your XP Disc and slipstream SP2 into the copy. There are many sites on the web to tell you how to do this. Google should turn up many, as this was the first hit:
You would now have the ability to repair your current installation.
SP2 has nothing to do with download speeds. You can not run two firewalls, not matter what you have. You can disable the SP2 firewall altogether and just run the Zone Alarm or vice versa. As far as speeds are concerned, I had 60mhz PII downloading at a full 3.0 Mbps so it has everyhting to do with configuration and nor the machine.
I would suggest you visit, www.dslreports.com and have your speed tested there and make some necessary corrections is their online tools tell you that some are needed.