@zeigs spud
Scope gave you some good advise, save for one piece: Norton is horrible. It's a memory whore, it runs/scans slowly, it slows down your PC significantly, the updates aren't very good, it misses many viruses, etc...
I own an IT security company, by the way.
First things first, hit start > run > msconfig > go to the startup tab. This is your startup list, the list of programs that run in the background 24/7. Disable everything you don't need. The shorter this list, the better. Things to leave on: your firewall and anti virus software, your ISP software (if required), and any drivers. Blank entries and suspicious system32 entries should absolutely be disabled. Apply and reboot. After reboot, you'll get a warning box (System Configuration Utility, you've made changes to the way windows starts up, blah blah blah); check the box for "don't show me this again" and hit OK.
Second, download Adaware SE (
http://www.download.com/3000-2144-10045910.html ) and SuperAntiSpyware (
http://downloads2.superantispyware.com/ ... pyware.exe ) . Do a full system scan with both and let me know how that goes.
Download HijackThis (
http://www.majorgeeks.com/download5554.html ) HijackThis will analyze your system and generate a report/log. Post this log here for me to read. With the hijackthis log, I can tell you what virus(es) you're dealing with and how to remove them.
After you've gotten this bug removed:
1) Don't pirate software via limewire. It's not only illegal but risky and stupid. There are better ways to pirate software, though I don't endorse doing so (cough azureus and torrentscan cough). Always scan downloaded files for viruses and spyware with an up-to-date scanner before opening them.
2) Keep backups! Stuff like this happens, and when it does, sometimes you end up loosing a lot of data. If you have backups, it's no problem; you just reformat and reload your data from backup.
@Scope,
Try Avast antivirus instead of Norton. It uses less ram, scans faster, updates more frequently, and is 100% free. It also has a more complete virus database.
Scanning from safe mode is useful in some cases, but diagnosing the problem can be done from within Windows without problems. The actual removal of the virus may need to be done from safe mode, though.
However, since zeigs spud said he's gettnig tons of popups and ads, I'd bet money this is spyware/adware, not a virus. That's why I told him to grab those antispyware scanners and hijackthis. The hijackthis log will tell us exactly what's wrong though. If it turns out to be a virus, I'll give him removal instructions and recommend that he install Avast for future protection, along with a decent firewall like Comodo.
Peace,
Pete Zaria.
PS - Isn't it sad that the Internet has evolved to a point where simple home computer users have to install multiple layers of protection just to surf the internet? I think we can blame this largely on Microsoft, since the open source (Linux, Unix, BSD) and Mac communities have no such problems. And Vista is just going to make it that much worse... Please don't get vista, btw. /end rant