Ubuntu inside VirtualBox is slow [closed]

There are a couple of things you can do.

• Reduce the memory you give to the VM to half your total system memory or less. If the host doesn't have enough memory to operate smoothly, it will affect the guest. Typically Windows needs more memory and Linux needs less.
• Enable VT extensions in the VBox settings. This uses hardware support built into your CPU if you have it available.
• Turn off desktop effects like Compiz in the VM guest. VBox 2.2.2 has support for 3D acceleration in VMs, but 3D still slows things down a little.

I hope this helps.

EDIT: Another thing you can do is run top in a terminal window in the VM and see if there's a particular process eating the CPU or memory.
Does Windows get slowed down when you have issues with the VM?

Have you installed Additions? They make quite a difference.

Here's how.

If this "...But I need access to the XP partition without having to reboot and hence the attempt..." is your REAL problem, then you can mount ntfs partions directly from Ubuntu(linux) with no problem. A quick google for "ubuntu ntfs" will give more details