Hey I'm looking for some FO3 mods and can't decide which to use, any recommendations?

Depends on what you want to get out of the game. If you want to up the challenge while giving yourself more stuff to do:

Fallout Wanderer's Edition
Mart's Mutant Mods

Others I would highly recommend to milk more out of the game:

Weapon Mod Kits
FO3 Re-designed (formerly Project Beauty)
Energy Visuals Enhanced
NMC's Texture Packs
DC Interiors

Those seven are what I consider "must have", but there are numerous others I like. Now getting them all to place nicely with each other takes some doing.