on *:TEXT:!roulette *:#: {
var %points = $readini(%pointsFile, $findID(%pointsFile, $nick), points)
if ($2 == null) {
msg $chan $nick you must input a whole number.
return 0
} else {
if (%points < 0) {
msg $chan $nick You can't roll if you have 0 points.
return 0
} else {
if ($1 == !roulette) { | if (!%rouletteflood) {
set -u20 %rouletteflood 1
var %roulette = $rand(1,2)

if (%roulette == 1) {
msg # $nick won 1 point in roulette and now has %points points!
writeini -n %pointsFile $findID(%pointsFile, $nick) points $calc(%points + 1)

return 0
}

elseif (%roulette == 2) {
msg # $nick lost 1 point in roulette and now has %points points!
writeini -n %pointsFile $findID(%pointsFile, $nick) points $calc(%points - 1)

return 0
}
}

Haven't tested this, but it should work. You must have this in your "variables" section, obviously with your location.

%pointsFile C:\Users\User\AppData\Roaming\mIRC/points.ini