OEM=Original Equipment Manufacturer. You're right on the money about it not coming in retail packaging---which is nice if you don't want the software for whatever reason. They typically ship with the drivers however.

From what you've listed, it looks good. I haven't used anything by Inno3D before, so I can't say how their quality is. I'm usually for Gainward, but this time it is a good idea to skip them. Their Ti4200 cards have had some serious issues and have resulted in bad cards. Last I checked Gainward hadn't fixed, nor offically addressed the issue. If you want my opinion on a solid company, I'd check out MSI. I've used a few of their video cards and motherboards before and they are solid. They're well priced and work great.

One thing I would suggest with the setup is getting 2 x 256MB sticks of DDR. The nForce 2 chipset has a dual-channel DDR configuration, and using 2 sticks of RAM is optimal with any nF2 board.

I don't know what OS you're using currently, but going to Windows 2000 or XP would help in the stability department.

Lastly, make sure to buy a good power supply. Don't get something cheap here. Buy something good, like ones from Antec or Sparkle. Typically 300W is the bare minimum you should go anymore, but I'd say 350W wouldn't hurt. 300W is fine as long as the power supply puts out at least 180W between the 3.3 and 5V rails (listed on the power supply sticker). Going cheap here is a bad idea, since a poor power supply can affect your stability.

Expect to pay $45-80USD (about 35-50 pounds I'm guessing over there).