well, I tried to install Ubuntu, but, there was a problem. I had the Errno 30 when I tried to install. I am using a LiveUSB to install the OS. ANd I am using an Inspiron 1525 (that's not a good computer). I tried the 32 bit version, 'cause my PC have only 2 GB o RAM. Could anyone help solve this problem? (sorry for bad English, I am Brazilian)
If Linux detects a problem on the harddrive, it will switch the filesystem to read only to prevent damage to the filesystem.
Since this is happening during install, I would assume something is wrong with the CD (ie. a bad ISO). You can find this out by running the 'check cd' option you get during boot. If this shows errors you need to re-download and re-burn the install disc.
If the installation disc turns out to be perfect it is likely to be a hardware problem. It could be your hard disc that is failing. Or if it is a desktop it could also be a faulty cable.
Source of this information.