cd/dvd driver won't read my cd/dvds

i just installed 2 new cd/dvd drives in my dell it says they are functioning properly but they wont read cd's or dvd's at all and suggestions am running XP

Nothing is more problematic than optical drives, except flash drives.
If you bought the basic optical drives that came with you Dell, it is very likely they have failed. If they are a year old, they are shot. Replace them with NEC, LG, Samsung, Pioneer, or Plextor.
If the machine is still under warranty, call Dell and get them replaced.

i replaced my dell drive with 2 new samsung dvd/cd drives but they wont read the cd's still i just got them 4days ago

What drives are they i.e. are they DVD burners or DVD/CD-RW combos? Also, how have you set them up i.e. which one is the master and which one is the slave? Are you sure the jumpers are set to the correct positions? In addition, have you tried updating the firmware for the drives? These need to be answered before we can proceed with the solution.

Double check your EIDE cables, and your jumpers. There are jumper pins on the back of each drive... the plugs are marked C S M for cable select, Slave, and Master. Be sure they are both cable select, or as I prefer, Master and slave...
If the jumpers are correct, assume you have a bad EIDE cable, and replace it. they cost about $3.00 most places. It is possible one of the cables was damaged during removal. It is easy to do.
Then if still not working, check your BIOS settings to see what the BIOS reports... then look at the Device Manager in Start -> Control Panel -> System -> Hardware -> Device manager to assure you don't have any red or yellow flags... and that the drives are both listed under DVD and CD Drives.

Will it boot from a bootable cd? If your BIOS is set for it to be able to boot off a cd and the drive won't it is either a cable problem, motherboard problem, or drive problem. If it does boot off a cd, you've got a Windows problem.