Hi all! Sorry if this is the wrong place to post this - it's my first time on here.
Basically my friend and I (he is really into pokemon) decided for christmas we would get together and battle pokemon from Crystal on the N64 using Stadium 2.
Since he is big on pokemon and although I really like pokemon haven't played at a while, he's at a big advantage and I need some big help building a better team.
Here's what I've come up with. Please tell me if it is good/bad and whether pokemon or moves should be changed. I'm training lots of pokemon so after the first round or two I can change the team up if need be.

My strategy is to pick good pokemon which have very few weaknesses, making it hard for him to exploit anything. Also, pls note we are not using legendaries

1) Skarmory (general strat is to set up curse, then spread the poison)
@Leftovers
-Drill Peck
-Curse
-Toxic
-Whirlwind

2) Kingdra (general strat is to get the double team up, then attack)
@Mintberry
-Double team
-Surf
-Ice Beam
-Rest

3) Forretress (Deal some tough damage then take hopefully take out something tough)
@???
-Earthquakes
-Spikes
-Rapid Spin
-Explosion

4) Lanturn (for anything which would hurt Forretress or Skar w/ fire)
@???
-Confuse Ray
-Thunderbolt
-Thunder wave
-Surf

5) Tyranitar (I know he has a lot of weaknesses, but he's a powerhouse, right?)
@???
-Rock Slide
-Crunch
-Earthquake
-Thunderbolt/Flamethrower?

6) Snorlax (If I'm having trouble, I send this big boy in to put him to bed)
@Leftovers
-Double-edge
-Earthquake
-Sleep Talk
-Rest

Other pokemon I have to use: Lapras, Dragonite, Jolteon, Alakazam, Arcanine, Donphan, Heracross, Marowak, Starmiem Ursaring, Wobbuffet, all eevee forms

All items are ??? if I don't know what to use. I only have 2 leftovers (how do I get more?).

You may ask why I've spent so much time on this? We've bet a copy of the new Pokemon B/W2 on the winner best out of 5.

Thanks in advance for the help!