which system to use?

Hi all,

just wanted to get a few opinions on which "system" to use, for the game that I play. ie count type, hi-low? ko?, betting spread/bankroll etc...

my current game that i play is

8 decks
75 percent pen
dealer stands soft 17
double any 2 cards
double after splitting
no resplit aces, aces get 1 card only
and the bet minx and max are $5-100 on the one table
and another table is somehting like $25 - 500 min and max

any help would be great guys
thanks in advance
matt