If you are not a gamer, and just need it for basic PC stuff (and not video editing and really high tech stuff), you should be able to get a very nice notebook which will last you a long time for under $1000. There are a lot of notebook brands that are very fine machines, so with notebooks I would look more at things like warrantees and customer service, and make sure they have a lot of USB ports. The technology is really moving so damn fast today, that the industry has most people convinced that they need a supercomputer for their everyday needs. 90% of what I do (and I am a tech guy who works on these damn things) could be done quite happily on the eight year old 400MHz laptop I just sold to a buddy. For me though that 10% and my need to be "up on the times" means I do have a pretty kickass system. The average user couild get by happily on an old machine like that lappy.
When it comes to which flavor of Windows, I strongly reccomend (especially if you are new to the PC) that you get Vista. I reccomend it to everyone except those who already have enough computer. It's buggy and I hate it, but it's the way of the future, and they are force feeding it to us, but in time and after a service pack or two it should get better. If you get a notebook you don't have XP as an option, and should you get a notebook and remove it and install XP, then you can kiss any warrantee goodbye. Probably same on any name brand desktop. We are all gonna have to get used to Vista sooner or later. If you do get Vista I STRONGLY reccomend no less than 2GB of RAM, and if the notebook you want doesn't come with it, just buy it its dirt cheap. A vista system with 512MB of Ram is like a sprinter trying to run a race with both legs in casts. Lastly, there are so many idiotic changes in the way Vista works from XP, that you might as well start unlearning any xp things you know and start learning Vista.
If you go desktop, I hear a lot of folks talk up Dells, but my personal experience is that they are junk, and when the parts break after the warrantee expires, often things are to proprietary to make fixing or upgrading economically feasable. 90% of the broken machines I fix are Dells. Ideally, if you have a techie friend, or a reputable local computer shop, I'd have them build it custom for you. If you want no hassle just buy it prefab and cheap I reccomend Gateway. HP can be OK, but I personally hate HP support (I have no experience with Dell support). Avoid Compaq (HP's budget line), eMachines, and just about anything else like the plague.
One last thing. If they give you anything with Norton Internet Security on it when you buy it, remove it post haste (if you can without downloading a special utility to remove it) and replace it with
AVG Antivirus,
Spybot S&D, and Lavasoft's
AdAware 2007. All of them are free, and do just as good of a job of protecting you, and they don't need an expra CPU and gig of ram to run them like Norton Bloatware does.
Do a LOT of reasearch, ands especially if you have a local shop build you a custom and work on it after purchase, because this industry is like the car mechanic deal. They smell dummies coming like sharks smell blood in the water, and they feed on them more ravenously. Most repair shops (and even geek squad) aren't at all what I'd call "honest bussinesses". Good luck, but in closing, three words:
RESEARCH, RESEARCH, REASEARCH!!!