I can make use of every weapon in the game except for sten and fg42. They don't fit very well for me.
As for classes... every class is good and I usually choose class depending on what map/objective we're playin'.
Playing covert: for accuracy the sten, smallest shot grouping, but very sensitive to movement and overheats quickly. For damage at close range the fg42 has great firerate and fair accuracy, better imo than thompson, but only holds 20 rounds per clip. FG42 is scoped and sten is not but I can get fair accuracy with sten by using binocs and firing quickly without moving weapon.
For sheer damage the panzerfaust, in skilled hands it can take out multiplayers at once, but is dangerous to use, especially indoors. If you can deal with having to resight after every shot the garand sniper rifle is good, but dont care for the sights and too much kick for me even at level 4 skills. If playing engi, I prefer the garand or k43 with grenade launcher, it can fire around corners like a billiard ball if you know how to use it, but in a closeup firefight is harder to aim. That should summarize nicely I think.
As a ref. I am expected to play whatever position is needed, tho my preference is for covie or fops.
Best weapon is thompson/mp40. Certain weapons are better but only in given situations, nothing is more all-round better than those. Worst i'd say is flamethrower unfortunately but it can still be a lot of fun in the right situations/use it well. Best class in general is medic, so far as shooting each other is concerned for the improved health and med packs. Engy is the spirit of E.T. though, and is best class to start with though cos you learn the objectives and maps better and it helps you appreciate the other classes too.