Shadow - Zen meditation techniques are just as you say - being mindful. Maintaining awareness and stopping the mind. For a long time I repressed thoughts in meditation, and I think many people take this approach, having never been shown anything different. Aikido meditation techniques are excellent for focussing the mind on the breath (also an integral part of Zen), my instructor does alot of chi-gung style meditation with his students as he also teaches Tai Chi and the two sets of meditation strategies work very well together.
My own practice is a mixture of Taoist meditations (standing, chi-gung) and zen style (in seiza.) The techniques are very different but also complimentary - the standing is very good for alowing the mind to clear and relaxing the body so that once you sit you are already in an open and aware state of mind.
Master Moy has often been quoted as saying that Tai Chi is just preparation for meditation and whilst aikido is much more dynamic it is also excellent preparation.
The thing I like especially about these systems is that they aren't connected to some 'higher being' this sort of dualistic visualisation is good, in my opinion, only for clouding the mind and cluttering it with nonsense. Meditation is all about stopping and seeing. As Nick put it. Just sit.