Sounds like you need to learn about fuses =)
In the Freeworlds mod, here is an entry we made for a destructable base in the shiparch.ini file:
[Solar
nickname = dreadnaught_destructable
type = MISSION_SATELLITE
DA_archetype = ships\swships\dreadnaught\dreadnaught.cmp
material_library = ships\swships\dreadnaught\dreadnaught.mat
material_library = fx\envmapbasic.mat
envmap_material = envmapbasic
LODranges = 0, 15000
mass = 10000.000000
open_sound = depot_open_sound
close_sound = depot_close_sound
solar_radius = 800
shape_name = NAV_outpost
hit_pts = 700000
destructible = true
fuse = fuse_dreadnaught_destructable, 0.000000, 1
The important line is the "fuse = fuse_dreadnaught_destructable, 0.000000, 1" line. You'll need to make a fuse if you want the really cool explosion effects. After you add the fuse line, then go into the DATA\FX\fuse.ini file, and create your fuse effect. Again for the Freeworlds mod, here is our entry in the fuse.ini file:
[fuse
name = fuse_dreadnaught_destructable
lifetime = 3.000000
death_fuse = true
[start_effect
effect = gf_piratestationexplode#2
hardpoint = HpEngine020
at_t = 0.150000
[start_effect
effect = explosion_sfx_csx_large03
hardpoint = HpWeapon03
at_t = 0.330000
[start_effect
effect = gf_piratestationexplode#2
hardpoint = HpWeapon04
at_t = 0.330000
[start_effect
effect = gf_piratestationexplode#1
hardpoint = HpWeapon05
at_t = 0.500000
[start_effect
effect = explosion_sfx_csx_large04
hardpoint = HpWeapon06
at_t = 0.700000
[start_effect
effect = gf_piratestationexplode#3
hardpoint = HpWeapon07
at_t = 0.800000
[start_effect
effect = gf_piratestationexplode#3
hardpoint = HpWeapon08
at_t = 0.800000
[start_effect
effect = explosion_sfx_csx_large05
hardpoint = HpEngine019
at_t = 0.800000
[destroy_root
at_t = 1.000000
You will need to do your own research on the different explosions, some of them are really big =) I would suggest fooling around with the fuses, see what you can learn, then if you have any questions, ask. But I will only answer your questions about fuses
after you have at least tried messing with them yourself. After you have looked into the fuse.ini file and tried to create your own fuse, if you have problems or questions, then ask.