Weather you will work with wood, metal or glass is important. Some types of drills are more suited to one of these materials than others. Also you can get drill bits made specifically for these types of materials. In most cases a bench top drill will easily make holes in any of these materials.
A benchtop drill press is most common for woodwork. They are relatively portable but still powerful enough to get the job done. A floor drill press on the other hand is much harder to relocate due its larger height. The floor drill can tackle much bigger workpeices due to its size. Ultimately you choose between weight and portability versus power. There's not much a bench drill can't do however, so if you're just starting out with woodwork it's a safe bet.
Even with the best drill press sometimes you will need some extra help. This is where add-ons and accessories can come in handy. You can use special nibblers for cutting metal sheets. Also, you could attach a sanding disc which can enable your drill to function as a sander.
No matter which brand you go for, you have should pick one that is well built. Make sure the individual parts that make up the machine are high quality steel. The column, the chuck, the base, all need to be rigid and robust. A poorly built machine is a safety hazard, and won't get the work done accurately.
Also consider what sort of chuck you want. There are several different options when it comes to the chuck for your drill press. In most cases it's better to have a chuck with a key, than one without. Having a good chuck key ensures that the drill bits remain tightly secured for accurate drilling.
Even the best drill press may come with faults on occasion. Although most of the well known brands, like WEN and SKIL are very high quality - to remain on the safe side, ensure they come with a good warranty. Final notes: Ultimately the decision of deciding which drill press is the best comes down to personal preference. However you should give the points noted above due consideration. This will ensure you don't waste money on a low quality tool.