Hi,
Maxtor is Seagate's budget brand now, not really worth looking at.
If you want performance without spending for a WD VelociRaptor, Seagate's 7200.11 series and Hitachi's 7K1000 series are worth looking at. The smallest drive is 500GB.
Western Digital's Caviar SE drive are very quiet and run cool, but painfully slow when doing more than one thing with them. There's probably a way to disable the quiet seeking feature over WD's maintenance application (the hard drive will seek faster) but I never got it to work over SATA.
The 7200.10 Seagates are quite good, but get very hot.
You can't really know about drive reliability over people's personal experience. In my case, I've only seen Maxtor and Toshiba drives failing. Others, mostly Seagate, mostly WD, etc. Hitachi's drives have been unreliable in the past, but they're quite good now. One thing is sure, if you have a proper PSU and cooling, you shouldn't have problems.