Ok..You can get your boot time by writing this command into the terminal :
`systemd-analyze`

To check how much time services are using :
`systemd-analyze blame | less `

To print the output to a file type :
`systemd-analyze blame > Boot.txt`

A *Boot.txt* file will be created in your home directory. You can then upload your file here so we can go through it and suggest you an optimal solution.

Meanwhile try to update your OS by :
`sudo apt-get update && sudo apt-get upgrade`