Re: /boot Partition
/boot can fit with lots of spare room on a 500MB partition. However, there are only a relatively few reasons why you would need to separate /boot from the "/" filesystem. So for a new installation, if you don't know of a solid reason why you need it, then don't bother making it separate.
To increase the size of an existing partition, you can boot a live CD and use GParted. Personally I like to use a Parted Magic Live USB stick, but you can use a GParted Live or Ubuntu or other Linux Live CD. However, you will have to free some space before you can expand the /boot partition -- like maybe shrink whatever is to the right of /boot by 100MB first, and slide it right on the drive so there is 100MB of unallocated space alongside the /boot partition.
Intel Core i7-950 / Asus P6X58D-E / Nvidia GTX480 / siduction 64-bit on OCZ Revodrive SSD / KDE4.10.2/ Kubuntu 13.04