Something is wrong with your computer.
1 - 64-bit versions of windows run 32-bit programs fine, the only things that don't work are drivers, since you cannot use 32-bit drivers in a 64-bit version of windows. Some things will install virtual drivers, for example korean MMO games using stuff like Gameguard/Hackshield. In all other cases, 32-bit programs work fine (assuming they're not really old games using a 16-bit installation program, as some used to do).
2 - Changing your OS will not void your warranty, the floor/phone people just tell you that because they don't want to deal with you. Read over the warranty, it shouldn't mention anything about changing the software on the machine. If you can confirm it doesn't mention that, call them and send it in to have it fixed. If they insist they can't and refuse, ask them for their name and employee ID number or station they work at or some other info, so you can take it up with a manager. That should change their mind real quick.
3 - Describe the disc you did a clean install from. If it's got ANY company logo on it (like dell/hp), then it's NOT a "clean" install disc, it's been modified. You should run the Magical Jellybean Key Finder (google it) to get your current product key, then do a clean install with an unmodified windows disc. You know, one of the ones that hasn't been fucked with by a company, one of the ones that still has the microsoft logo and shiny designs on it. It doesn't matter which "version" disc you use, as long as it's a 64-bit disc. Home basic, home premium, business, ultimate, it doesn't matter which disc you use since every disc has info from every version, which version is installed depends on the key you give it.
