STR as such means a lot to a fighter. Basically it's the "thing" which lets you hurt 'them' bad. The higher the better, though it's tricky to roll 18/00. Some statistic people will probably give you the odds too, I personally never cared about the odds..
So yes, the higher you can get it, the better (18/00 stands for 18/100, just the display limit or something, or one of those creepy rules again). Definately try to get DEX and CON maxed out, that is to 18 (depending on the race, some have one or another higher). I personally sacrified CHA to get other stats up, mainly because in BG1 (where I started with this char) and BG2 the money, or lack of it, is just a temporary inconvenience and eventually you will have more cash then you can spend, and I didn't have much troubles at all to keep the group members "at bay". And in BG2 you will get one CHA booster soon enough to worry even about the prices.
STR, DEX and CON are your main stats, do not ignore those. INT and WIS are secondary, though from those 2 I would probably suggest to keep WIS higher, as it seems to affect some dialogue choices and such. Or so they say.
I play human berserker, and I like it a lot
