virtualbox.org

I have had these VM's on my host for a while, but its been acting very erratic of late, to the point where I have been unable to use them.
When I boot the Machine, after the virtual box screen, I get a scrambled Oracle logo, but it still proceeds to the starting Windows screen, it takes ages for the
graphic display to come up. When I finally get to the windows welcome page,it lags for about 5 minutes before playing the welcome sound which is glitchy/stuttered.
Performance is terrible as it freezes for no apparent reason and I simply ca't do anything. I have XP machines on it too and they run without any issue.
When I use the power button to stop or restart it it stays stuck: " on waiting explorer.exe to stop . . . Playing log off sound "
This only started some weeks ago and I have tried everything I can to fix it with no success.
Can anyone help?

Please read the following: Minimum information needed for assistance.

The version of VirtualBox you are using, and whether you have installed the Guest Additions (in the guest).
VirtualBox-5.1.16-113841 and Yes I have guest additions installed

Host & Guest make and version including 32 or 64 bit, and the amount of memory available to both.
Host is a Windows 8.1 64 bit corei5 with 8gb of ram
Guest is a Windows 7 VM I have assigned 2gb of ram to

I have attached the log files requested

I tried attaching the VBoxHardening.log file, but it says file is too large.

Are the details provided enough?
Or is more needed?

00:01:25.315346 VMMDev: Guest Additions information report: Version 5.0.14 r105127 '5.0.14'

You should update your GAs to the current version.

00:00:08.770295 GUI: 2D video acceleration is disabled

The same for 3D. You should enable them and then update the GAs.

00:00:05.300662 VRamSize <integer> = 0x0000000001200000 (18 874 368, 18 MB)

You should increase the vRAM to 128, if not 256 MB.

Thanks, seems to be a whole lot better now.
Still freezing a bit but its a lot better than it was .

You have a dual core host with 2GB, so the guest is using a 1GB and a max of 1 core - and even physical systems with that spec will have moments of high latency.

Once again thanks.
Really appreciate the help rendered.