Buying new desktop computer?

I've just gotten into the small business scene in the last year and having taken Journalism in post-secondary, I'm not quite sure what I'm looking for.

The computer I have now runs like it is 20 years old and no amount of scanning and defragging has helped. I've taken it in for sweeps and scans and even that finds nothing. I just put AVAST! Antivirus on and it says that there is a virus in the memory.

I just want to buy a new computer. I'll be using it for research, invoicing, company email, etc.

What should I look for when looking at new desktop computers? Any specific brand better than others?

Buying new desktop computer?systemworks

This level of computer would probably be good for you unless you plan on gaming or running any memory hogging programs. (If you do either of these I would suggest 1gb of ram). And whatever you do don't get Vista with less than 1gb of ram.

http://www.bestbuy.com/site/olspage.jsp?...

Buying new desktop computer?windows

My advice would be to get a laptop. Desktops are good for gamers because they have more performance. Laptop sacrifice a little bit of that performance for portability but have integrated wifi for using the internet. This way you can do the simple tasks you describe on the go. And by simple I mean not requiring a lot of performance, not easy.
Before you buy a new one, why not format the hard-drive and re-install Windows? Unless you have a virus that has infected the Flash memory (very rare) formatting will remove all viruses and malware.