RAID-? (Need advice)

Okay guys, I have a single 250GB SATA150 WD and kind of want to start a RAID. I know these aren't the fastest drives (load times on UT2k4, Myst V Demo, and Stepmania are sort of slow), and I've got a little cash (not a LOT, so only stuff less than 10k RPM) to throw around, so I need some advice.

Terms: Great CPU/Gfx card/RAM, and I'm looking for a setup that'll be efficient for large games. Also, I have a bunch (~100GB) of movies/music/warez that I would really like to keep secure in case of a crash.

Options:
- Get 2x 250GB and do a RAID-5. ($230)
- Get 2x 250GB and do a RAID-4. ($230)
- Get 2x 160GB and do a RAID-0 for just games and boot (really fast?), and keep existing 250GB for storage. (Maybe RAID-1 later) ($170)
- More good options?

Thanks to anyone that can help.

No idea on Hitachi but I personally go for Segate and Samsung and make sure they're always warm to the touch or cooler.  Heat = bad for all brands.

If you're using XP/2K/2K3 server edition, you can do software RAID.  It'll definitely incur CPU cost but unless you spend some pretty money a good RAID card, there's reliability issues on the RAID controller itself.  Motherboard RAIDs are pretty notorious for suddenly not working, as are the cheaper RAID cards.  And because it's done in hardware, you might not be able to just take a HD from the RAID and plug it in else were.

Don't recommend the plain RAID-0 striping unless you really don't mind risking everything on it.  And if that's the case, you can get away with two, much smaller drive at cheaper prices.  Don't you need at least three drives to do the higher RAIDs?