Can't install Ubuntu on my computer

I originally had a windows computer and then I did a flash drive dual boot for a bit. One day I had to re-download Ubuntu, but then it cleared my Windows hard drive completely. I don't want to be on windows anymore, so that's okay with me. I just want to be able to work in Ubuntu. The main issue is when I restart my computer after installing Ubuntu from the GRUB menu I now get from restarting, it doesn't give me the option to use Ubuntu. Only 1. Try Ubuntu without installing 2. Install Ubuntu 3. DEM Install, and 4. Check disc for defects. When I first dual booted it let me install, and then I restarted and then I could continue in Ubuntu. The option would change from install Ubuntu, to just Ubuntu, now it no longer does that. Is there a way I have to partition my hard drive or do I just have to keep trying Ubuntu without installing. I really don't want to have to keep doing that, because then I'll just lose my data each reboot. This is totally my fault, for installing Ubuntu and erasing a disk, I just want to be able to use install Ubuntu and use it continuously. Any help would be appreciated.

I tried the lsb and and the package version in terminal, but both said I didn't have any.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubiquity 2.21.63.2
ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13
Uname: Linux 4.4.0-31-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CasperVersion: 1.376
Date: Sun Feb 19 20:34:10 2017
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz.efi file=/cdrom/preseed/ubuntu.seed cdrom-detect/try-usb=true noprompt floppy.allowed_drive_mask=0 ignore_uuid boot=casper quiet splash ---
LiveMediaBuild: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)