okay first off ram, i have two choices

Transcend DDR 400 or Kingston DDr400 ? which is better i dont know transcend well though

secondly

i have to choose between these hdds

Seagate 120Gb Barracuda 4 ATA 100 2mb cache R945
Maxtor 120gb ata 133 2mb cache/ 8m cache R945/ R 1035
WDcaviar se 120Gb 8mb cache ata 100 3 yr warrnty R1095
Hitachi Deskstar 120Gb 8mb cahce 3 year warrnty R?

i would like the seagate as i have an old one and they are good as far as i have read and seen and it is the cheapest, those numbers on the right are prices in my currency, divid by about 7.8 to get a dollar value. Also the seagate is the cheapest but it only has a 2mb cache and ata100 will thtatmake a big difference?