Security Pack 3
Once all the updates have been carried out, it's time to install an antivirus to protect your system from viruses and such. If, through the updates, you had Microsoft Security Essentials installed, then you already have an antivirus to rely on. However, if you don't have it installed, then you can download it here:
Microsoft Security Essentials
If you prefer something else, there's Avast:
There's also Avira:
All three are light and have good detection rates. So you can choose any one of them. The important thing is that you have one good antivirus ... and only one good antivirus. More than one, and your Windows may have worse issues than before.
And don't forget to update its database to the latest version (whichever antivirus you choose).
Hopefully, by now, you have the latest version of Internet Explorer for XP installed (Internet Explorer 8). If, by any chance, you didn't get this through the updates, then grab one here:
Internet Explorer 8
Feel free to download all essentials that you believe you need. If you need help here, let me know.
It's important that you have all essential programs and products up to date. Whether it's Java or whatever Adobe products or plugins you use. Make sure you have them all updated.
Just remember, though, to download from the official sites for such products. If you're not sure where to download whatever it is you wish to download, then please let me know and I'll help out.
When all is done, post here again so we may move on to the next step.