I am using kubuntu 16.04 on this PC
(http://www.hpshopping.in/HP_Pavilion_Notebook_-_15-ab549tx)
The two problems that I am facing are:

1. On startup this shows up 
http://imgur.com/qwktsyd
http://imgur.com/HMX349L
before the login screen. At times it is just stops
at this screen and doesn't move to the login screen. Or while shutdowning it stops 
at this screen.

2.Wifi issue:
It doesn't discover wifi at times and keeps getting disconnected randomly.
Also, when I am connected to a WiFi works very slow. But things go smooth 
when I boot into windows.
Information about wireless card:
abhishek@hp:~$ sudo lshw | grep wireless
                   description: Bluetooth wireless interface
                capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
                configuration: broadcast=yes driver=rtl8723be driverversion=4.4.0-22-generic firmware=N/A ip=192.168.1.13 latency=0 link=yes multicast=yes wireless=IEEE 802.11bgn
When I have tried so far:
1.
sudo add-apt-repository ppa:hanipouspilot/rtlwifi   
sudo apt-get update    
sudo apt-get install rtlwifi-new-dkms linux-firmware

2. The first solution from http://www.dedoimedo.com/computers/ubuntu-trusty-realtek.html
Didn't try the second one because I will have to recompile with each kernel update
then.