So my computer is 8 years old and it's dying. It's crappy and goes really slow. I click the Firefox icon and it takes about 30 seconds or longer to come up. Sometimes it will randomly say Firefox is not responding (or other programs). It's old...has 256MB of ram, 40GB hard drive...etc basically old shitty stuff. I'm looking for a new computer that is decent. I don't want the cheapest one available, but would preferably not want to spend like over 700 or 800 bucks. Basically what I need this comp is for basic school stuff (Word processing...etc), internet, and that's pretty much it. All I do on my computer is look at stuff online, download/listen to music, and talk to people on IM. I don't play games (other than stupid little online ones and the only game I would really want to play is Roller Coaster Tycoon 3 and that came out awhile ago so should be ok).
Also, I have another question. I have a second hard drive in my shitty comp now that is 160GB and exclusively for music. I bought this and installed it a couple of years ago myself and am wondering if I can just take it out and transfer it to my new pc when I get one if it will be ok and work and have all my stuff on it (I have over 20,000 songs I don't want to lose

).
Basically, computer for just browsing the next and listening to tunes, one that isn't super cheap (like how you can buy comps for like $399 that come with everything) and one that isn't over $800. Also, I really don't need everything just a tower would do fine (I saw some online for like 500-600 bucks that looked decent for what I do but I dunno recommend me some!)
Thanks dudes!