Extra $150??, NO WAY! Don't even think about it. The animated desktop (Dreamscene) and a few paltry 'extras' are all Ultimate really offers, along with some advanced backup, drive encryption, and some remote desktop options and maybe another tidbit here or there - none of which are worth that kind of money unless you absolutely need to have it.
Your main decision should be 32 bit or 64 bit - 64 is very compatible now, driver and software support is nearing 100% - lot of us are using it with the extra RAM 64 bit will allow.