Can't believe no one has mentioned a VR3 yet!!
Seriously, I would suggest a gekko, or similar for what you describe. If you choose to move on from that point, then you can use it as a backup gauge for deep dives (I use my Smart Pro for that purpose).
Suuntos are ideal first computers. Oceanic have bought out a range to rival Suunto but I haven't dived with them yet so I don't know what they are like yet. However Suunto.....