I've seen a lot of posts on these classes but I still don't know if
they're any good or not. My new party is now about Lvl 8-9 and I'm
really not impressed with the Samurai or the Ranger. maybe I've not
been raizing the proper stats? What's the feeling on these guys and how
have y'all made them effective in your parties?
(The party consists of; 2 Samurai, Ranger, Achemist, 2 Bishops)

Don't expect them to be masters at such low level, because they are hybrids. If you want them to become better earlier, you should focus on putting more points on a skill each levelup. If you spread the skills too much, they will take much longer to develop.

I have heard many good things about ranger and samurai too, mainly because of their ability to get instant kills. If you like instant kills, then put points in critical skill for samurai or ranged combat for ranger.

Yeah, I think I might have developed them wrong. I didn't put
enough points into the Senses for Samurai for example.
Where should I spend my points for these two professions?
I find they both pass-out during long combats since their stamina
is low. So where do I stick those 6 points?

Ranger: Senses is first priority. Senses is most important stat for rangestrike, and will unlock eagle eye, which is great for rangers.
As second skill, i usually pump dexterity. Raises number of attacks and to-hit.
Needed skills: Bow and ranged combat. Thats about it. Well, and maybe alchemy.

Samurai: I'd pump strenght (for damage and to-hit) and dexterity (for to-hit and number of attacks).
Check your number of attacks from time to time. At start, using two weapons is very good. But at some point, i could have 2 attacks with 2 swings with the primary weapon, if i don't use a secondary one. So i stop dual wield for a while. Later, when sword skill is at ~100, i can switch to dual wield again without loosing primary attacks.

Note: Since you have two bishops, you should be able to cast haste in all heavy fights later, so you don't need to push speed.

Stamina problem? You have 3 characters that use up lots of stamina (especially later, when the ranger gets many shots with xbows). But with two bishops, just buy Rest All books, and cast it when necessary.

Thanks Wereboar! That should help. I did change the 2 Samurai from
Felpurr to Lizardmen. The extra vitality helped and they are doing
more damage.