Don't get the 9500GT, really crap card

The Radeon 4850 is a good card if you can get it for <£100.
The Radeon 4830 is also decent.
If you really want a Nvidia card, for £100, I'd recommend
http://www.scan.co.uk/Products/512MB-XF ... -E-20-(x16)-2200MHz-GDDR3-GPU-738MHz-128-Cores-2x-DL-DVI-I-HDTV
Although XFX are not known for their RMA process.
If you are willing to spend a little more, get
http://www.scan.co.uk/Products/896MB-EVGA-GTX-260-SSC-PCI-E-20-(x16)-Mem-2106-MHz-GPU-626-MHz-192-Cores-2-x-DL-DVI-HDTVI have one similar, it is fantastic - very quiet and runs everything at 1900x1200 (24"+), plus I paid £200 for mine before christmas so that's a bargain.