drillholemetal
I purchased a wheel set and the bracket has a hole drilled in the wrong place. I need to make the hole larger.
Will a titanium bit (like the link below) drill thru a 1/8" or 3/16" steel bracket? If not, what do you sugggest to make the hole larger?
Bracket: 
If you are wary of making the holes larger (which is possible and as Tester101 says just make the hole in the tile larger) then you could just go for a smaller anchor and screw.
Obviously this will depend on whether the smaller screws are still a good fit for the holes in the hook. Also the load the hook can take might be reduced, but as you're not going to be swinging from it (hopefully!) you should be OK.
Ecnerwal raises a good point - I would want to know for sure what it is before drilling through it. Metal plates are often put in around wires and pipes specifically to stop you from accidentally drilling into them - you could break electrical wires or plumbing, potentially causing a fire or a flood.
The plates work like this image shows:
The best thing to do here probably isnt applying more force - either drill somewhere else, or open up a small hole in the wall around it so you can see what you are breaking, then decide if its still a good idea.
As for what will drill through it - it depends on exactly what it is and how thick it is. Drilling through strong thick steel requires lubricating oil so you dont overheat and damage the drill bits. They will dull very fast without it.
Best Answer
If you're referring to the hole at top center in your photo, you'd have a hard time drilling a new hole halfway overlapping an old hole. A better approach would be a rotary grinding tool. Any abrasive grinding bit will allow you to enlarge the hole enough to get the bolt through.
Be aware that this will tend to heat the part being worked. A damp rag on the part near the hole will absorb heat and prevent paint damage.
Alternatively, clamp a scrap bar over the original bar and drill through both. The scrap bar will act as a drill guide. You can use any high-speed steel bits available. There's no need for titanium or other exotic stuff.